url: do not reuse a non-tls starttls connection if new requires TLS#21082
Closed
bagder wants to merge 1 commit into
Closed
url: do not reuse a non-tls starttls connection if new requires TLS#21082bagder wants to merge 1 commit into
bagder wants to merge 1 commit into
Conversation
There was a problem hiding this comment.
Pull request overview
This PR updates connection reuse matching in lib/url.c to avoid reusing an existing clear-text connection for STARTTLS-style protocols when the new transfer requires TLS, preventing an unsafe/incompatible reuse.
Changes:
- Add a
req_tlsflag to the connection-match struct to represent “TLS is required for a clear-text STARTTLS scheme”. - Reject reuse of non-SSL connections when
req_tlsis set, even if the scheme itself is non-SSL (STARTTLS case). - Initialize
req_tlsfromdata->set.use_sslduring reuse candidate selection.
💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.
icanhasmath
pushed a commit
to ActiveState/curl
that referenced
this pull request
May 29, 2026
… requires TLS Reported-by: Arkadi Vainbrand Closes curl#21082 (cherry picked from commit 507e7be) Backport to 8.17.0 to address CVE-2026-4873 (a connection requiring TLS could reuse an existing unencrypted connection from the pool for IMAP, POP3 and SMTP, bypassing the TLS requirement). Cherry-pick applied cleanly; git's 3-way merge mapped the hunks onto 8.17.0's ConnectionExists()/conn->handler naming.
outcast36
pushed a commit
to greearb/curl
that referenced
this pull request
Jun 3, 2026
Reported-by: Arkadi Vainbrand Closes curl#21082
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
No description provided.