Fix invalid memory access in RESTORE with malformed zipmap (CVE-2026-25243)#3619
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…25243) Root cause: zipmapValidateIntegrity() and zipmapNext() use different methods to calculate pointer advancement for length-encoded fields. Validation reads the actual encoded size via zipmapGetEncodedLengthSize() (which returns 5 for the 0xFE prefix), but zipmapRawKeyLength() (used by zipmapNext during hash conversion) recalculates via zipmapEncodeLength() which returns 1 for decoded lengths < 254. A crafted zipmap with an overlong 5-byte encoding for a small length passes validation but causes a 4-byte pointer mismatch in zipmapNext(), leading to heap buffer over-reads during the zipmap-to-listpack conversion. Fix: add sanity checks in zipmapValidateIntegrity() to reject entries where the decoded length < ZIPMAP_BIGLEN (254) but the encoding uses more than 1 byte. This is applied to both field-name and value lengths. Test: added a regression test in tests/unit/dump.tcl that crafts a RESTORE payload with a 2-entry zipmap where the first field uses an overlong 5-byte length encoding for value 3. Post-patch, this is cleanly rejected by zipmapValidateIntegrity(). Pre-patch, the misaligned zipmapNext() reads garbage (confirmed via server log: "Hash zipmap with dup elements, or big length (0)") which also produces an error, so the test serves as a defense-in-depth regression anchor rather than a strict pass/fail differentiator. The actual heap over-read is detectable with AddressSanitizer builds. Signed-off-by: ikolomi <ikolomin@amazon.com>
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## unstable #3619 +/- ##
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+ Coverage 76.55% 76.67% +0.11%
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Files 162 162
Lines 80612 80614 +2
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+ Hits 61714 61812 +98
+ Misses 18898 18802 -96
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madolson
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May 5, 2026
sarthakaggarwal97
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May 10, 2026
…25243) (valkey-io#3619) Root cause: zipmapValidateIntegrity() and zipmapNext() use different methods to calculate pointer advancement for length-encoded fields. Validation reads the actual encoded size via zipmapGetEncodedLengthSize() (which returns 5 for the 0xFE prefix), but zipmapRawKeyLength() (used by zipmapNext during hash conversion) recalculates via zipmapEncodeLength() which returns 1 for decoded lengths < 254. A crafted zipmap with an overlong 5-byte encoding for a small length passes validation but causes a 4-byte pointer mismatch in zipmapNext(), leading to heap buffer over-reads during the zipmap-to-listpack conversion. Fix: add sanity checks in zipmapValidateIntegrity() to reject entries where the decoded length < ZIPMAP_BIGLEN (254) but the encoding uses more than 1 byte. This is applied to both field-name and value lengths. Test: added a regression test in tests/unit/dump.tcl that crafts a RESTORE payload with a 2-entry zipmap where the first field uses an overlong 5-byte length encoding for value 3. Post-patch, this is cleanly rejected by zipmapValidateIntegrity(). Pre-patch, the misaligned zipmapNext() reads garbage (confirmed via server log: "Hash zipmap with dup elements, or big length (0)") which also produces an error, so the test serves as a defense-in-depth regression anchor rather than a strict pass/fail differentiator. The actual heap over-read is detectable with AddressSanitizer builds. Signed-off-by: ikolomi <ikolomin@amazon.com> Co-authored-by: ikolomi <ikolomin@amazon.com>
lucasyonge
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May 11, 2026
…25243) (#3619) Root cause: zipmapValidateIntegrity() and zipmapNext() use different methods to calculate pointer advancement for length-encoded fields. Validation reads the actual encoded size via zipmapGetEncodedLengthSize() (which returns 5 for the 0xFE prefix), but zipmapRawKeyLength() (used by zipmapNext during hash conversion) recalculates via zipmapEncodeLength() which returns 1 for decoded lengths < 254. A crafted zipmap with an overlong 5-byte encoding for a small length passes validation but causes a 4-byte pointer mismatch in zipmapNext(), leading to heap buffer over-reads during the zipmap-to-listpack conversion. Fix: add sanity checks in zipmapValidateIntegrity() to reject entries where the decoded length < ZIPMAP_BIGLEN (254) but the encoding uses more than 1 byte. This is applied to both field-name and value lengths. Test: added a regression test in tests/unit/dump.tcl that crafts a RESTORE payload with a 2-entry zipmap where the first field uses an overlong 5-byte length encoding for value 3. Post-patch, this is cleanly rejected by zipmapValidateIntegrity(). Pre-patch, the misaligned zipmapNext() reads garbage (confirmed via server log: "Hash zipmap with dup elements, or big length (0)") which also produces an error, so the test serves as a defense-in-depth regression anchor rather than a strict pass/fail differentiator. The actual heap over-read is detectable with AddressSanitizer builds. Signed-off-by: ikolomi <ikolomin@amazon.com> Co-authored-by: ikolomi <ikolomin@amazon.com>
valkeyrie-ops Bot
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May 18, 2026
…25243) (#3619) Root cause: zipmapValidateIntegrity() and zipmapNext() use different methods to calculate pointer advancement for length-encoded fields. Validation reads the actual encoded size via zipmapGetEncodedLengthSize() (which returns 5 for the 0xFE prefix), but zipmapRawKeyLength() (used by zipmapNext during hash conversion) recalculates via zipmapEncodeLength() which returns 1 for decoded lengths < 254. A crafted zipmap with an overlong 5-byte encoding for a small length passes validation but causes a 4-byte pointer mismatch in zipmapNext(), leading to heap buffer over-reads during the zipmap-to-listpack conversion. Fix: add sanity checks in zipmapValidateIntegrity() to reject entries where the decoded length < ZIPMAP_BIGLEN (254) but the encoding uses more than 1 byte. This is applied to both field-name and value lengths. Test: added a regression test in tests/unit/dump.tcl that crafts a RESTORE payload with a 2-entry zipmap where the first field uses an overlong 5-byte length encoding for value 3. Post-patch, this is cleanly rejected by zipmapValidateIntegrity(). Pre-patch, the misaligned zipmapNext() reads garbage (confirmed via server log: "Hash zipmap with dup elements, or big length (0)") which also produces an error, so the test serves as a defense-in-depth regression anchor rather than a strict pass/fail differentiator. The actual heap over-read is detectable with AddressSanitizer builds. Signed-off-by: ikolomi <ikolomin@amazon.com> Co-authored-by: ikolomi <ikolomin@amazon.com>
madolson
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May 19, 2026
…25243) (#3619) Root cause: zipmapValidateIntegrity() and zipmapNext() use different methods to calculate pointer advancement for length-encoded fields. Validation reads the actual encoded size via zipmapGetEncodedLengthSize() (which returns 5 for the 0xFE prefix), but zipmapRawKeyLength() (used by zipmapNext during hash conversion) recalculates via zipmapEncodeLength() which returns 1 for decoded lengths < 254. A crafted zipmap with an overlong 5-byte encoding for a small length passes validation but causes a 4-byte pointer mismatch in zipmapNext(), leading to heap buffer over-reads during the zipmap-to-listpack conversion. Fix: add sanity checks in zipmapValidateIntegrity() to reject entries where the decoded length < ZIPMAP_BIGLEN (254) but the encoding uses more than 1 byte. This is applied to both field-name and value lengths. Test: added a regression test in tests/unit/dump.tcl that crafts a RESTORE payload with a 2-entry zipmap where the first field uses an overlong 5-byte length encoding for value 3. Post-patch, this is cleanly rejected by zipmapValidateIntegrity(). Pre-patch, the misaligned zipmapNext() reads garbage (confirmed via server log: "Hash zipmap with dup elements, or big length (0)") which also produces an error, so the test serves as a defense-in-depth regression anchor rather than a strict pass/fail differentiator. The actual heap over-read is detectable with AddressSanitizer builds. Signed-off-by: ikolomi <ikolomin@amazon.com> Co-authored-by: ikolomi <ikolomin@amazon.com>
valkeyrie-ops Bot
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May 19, 2026
…25243) (#3619) Root cause: zipmapValidateIntegrity() and zipmapNext() use different methods to calculate pointer advancement for length-encoded fields. Validation reads the actual encoded size via zipmapGetEncodedLengthSize() (which returns 5 for the 0xFE prefix), but zipmapRawKeyLength() (used by zipmapNext during hash conversion) recalculates via zipmapEncodeLength() which returns 1 for decoded lengths < 254. A crafted zipmap with an overlong 5-byte encoding for a small length passes validation but causes a 4-byte pointer mismatch in zipmapNext(), leading to heap buffer over-reads during the zipmap-to-listpack conversion. Fix: add sanity checks in zipmapValidateIntegrity() to reject entries where the decoded length < ZIPMAP_BIGLEN (254) but the encoding uses more than 1 byte. This is applied to both field-name and value lengths. Test: added a regression test in tests/unit/dump.tcl that crafts a RESTORE payload with a 2-entry zipmap where the first field uses an overlong 5-byte length encoding for value 3. Post-patch, this is cleanly rejected by zipmapValidateIntegrity(). Pre-patch, the misaligned zipmapNext() reads garbage (confirmed via server log: "Hash zipmap with dup elements, or big length (0)") which also produces an error, so the test serves as a defense-in-depth regression anchor rather than a strict pass/fail differentiator. The actual heap over-read is detectable with AddressSanitizer builds. Signed-off-by: ikolomi <ikolomin@amazon.com> Co-authored-by: ikolomi <ikolomin@amazon.com>
valkeyrie-ops Bot
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May 29, 2026
…25243) (#3619) Root cause: zipmapValidateIntegrity() and zipmapNext() use different methods to calculate pointer advancement for length-encoded fields. Validation reads the actual encoded size via zipmapGetEncodedLengthSize() (which returns 5 for the 0xFE prefix), but zipmapRawKeyLength() (used by zipmapNext during hash conversion) recalculates via zipmapEncodeLength() which returns 1 for decoded lengths < 254. A crafted zipmap with an overlong 5-byte encoding for a small length passes validation but causes a 4-byte pointer mismatch in zipmapNext(), leading to heap buffer over-reads during the zipmap-to-listpack conversion. Fix: add sanity checks in zipmapValidateIntegrity() to reject entries where the decoded length < ZIPMAP_BIGLEN (254) but the encoding uses more than 1 byte. This is applied to both field-name and value lengths. Test: added a regression test in tests/unit/dump.tcl that crafts a RESTORE payload with a 2-entry zipmap where the first field uses an overlong 5-byte length encoding for value 3. Post-patch, this is cleanly rejected by zipmapValidateIntegrity(). Pre-patch, the misaligned zipmapNext() reads garbage (confirmed via server log: "Hash zipmap with dup elements, or big length (0)") which also produces an error, so the test serves as a defense-in-depth regression anchor rather than a strict pass/fail differentiator. The actual heap over-read is detectable with AddressSanitizer builds. Signed-off-by: ikolomi <ikolomin@amazon.com> Co-authored-by: ikolomi <ikolomin@amazon.com>
sarthakaggarwal97
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Jun 17, 2026
…25243) (#3619) Root cause: zipmapValidateIntegrity() and zipmapNext() use different methods to calculate pointer advancement for length-encoded fields. Validation reads the actual encoded size via zipmapGetEncodedLengthSize() (which returns 5 for the 0xFE prefix), but zipmapRawKeyLength() (used by zipmapNext during hash conversion) recalculates via zipmapEncodeLength() which returns 1 for decoded lengths < 254. A crafted zipmap with an overlong 5-byte encoding for a small length passes validation but causes a 4-byte pointer mismatch in zipmapNext(), leading to heap buffer over-reads during the zipmap-to-listpack conversion. Fix: add sanity checks in zipmapValidateIntegrity() to reject entries where the decoded length < ZIPMAP_BIGLEN (254) but the encoding uses more than 1 byte. This is applied to both field-name and value lengths. Test: added a regression test in tests/unit/dump.tcl that crafts a RESTORE payload with a 2-entry zipmap where the first field uses an overlong 5-byte length encoding for value 3. Post-patch, this is cleanly rejected by zipmapValidateIntegrity(). Pre-patch, the misaligned zipmapNext() reads garbage (confirmed via server log: "Hash zipmap with dup elements, or big length (0)") which also produces an error, so the test serves as a defense-in-depth regression anchor rather than a strict pass/fail differentiator. The actual heap over-read is detectable with AddressSanitizer builds. Signed-off-by: ikolomi <ikolomin@amazon.com> Co-authored-by: ikolomi <ikolomin@amazon.com>
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Root cause: zipmapValidateIntegrity() and zipmapNext() use different methods to calculate pointer advancement for length-encoded fields. Validation reads the actual encoded size via zipmapGetEncodedLengthSize() (which returns 5 for the 0xFE prefix), but zipmapRawKeyLength() (used by zipmapNext during hash conversion) recalculates via zipmapEncodeLength() which returns 1 for decoded lengths < 254. A crafted zipmap with an overlong 5-byte encoding for a small length passes validation but causes a 4-byte pointer mismatch in zipmapNext(), leading to heap buffer over-reads during the zipmap-to-listpack conversion.
Fix: add sanity checks in zipmapValidateIntegrity() to reject entries where the decoded length < ZIPMAP_BIGLEN (254) but the encoding uses more than 1 byte. This is applied to both field-name and value lengths.
Test: added a regression test in tests/unit/dump.tcl that crafts a RESTORE payload with a 2-entry zipmap where the first field uses an overlong 5-byte length encoding for value 3. Post-patch, this is cleanly rejected by zipmapValidateIntegrity(). Pre-patch, the misaligned zipmapNext() reads garbage (confirmed via server log: "Hash zipmap with dup elements, or big length (0)") which also produces an error, so the test serves as a defense-in-depth regression anchor rather than a strict pass/fail differentiator. The actual heap over-read is detectable with AddressSanitizer builds.