Bug 2496748

Summary:	CVE-2026-54891 erlang: Erlang SSL: Unauthenticated data injection during TLS handshake [fedora-all]
Product:	[Fedora] Fedora	Reporter:	Ganesh <gnaik>
Component:	erlang	Assignee:	Peter Lemenkov <lemenkov>
Status:	CLOSED ERRATA	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	low	Docs Contact:
Priority:	low
Version:	rawhide	CC:	jonathan, lemenkov, rhbugs, rjones
Target Milestone:	---	Keywords:	Security, SecurityTracking
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:	{"flaws": ["39003d39-bd2e-4383-b8ef-25a6118d86aa"]}
Fixed In Version:	erlang-26.2.5.21-4.fc43 erlang-26.2.5.21-4.fc44	Doc Type:	---
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2026-07-19 03:55:56 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	2496625

Description Ganesh 2026-07-03 06:37:57 UTC

Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

Improper Enforcement of Message Integrity During Transmission in a Communication Channel vulnerability in Erlang/OTP ssl (tls_gen_connection module) allows a network-positioned attacker to inject unauthenticated plaintext that the TLS client application later treats as authenticated server data.

The function tls_gen_connection:handle_protocol_record/3 rejects APPLICATION_DATA records that arrive in pre-handshake states when the TLS endpoint acts as a server, but does not apply the same check when the endpoint acts as a client. A network-positioned attacker can send plaintext APPLICATION_DATA records to the client during the handshake. The records are buffered and, once the handshake completes successfully, delivered to the application as if they were authenticated post-handshake data. The attacker cannot observe the client's response or steer the connection, so the impact is limited to blind injection of unauthenticated bytes. The injection window is wider for TLS versions prior to TLS 1.3 than for TLS 1.3.

This vulnerability is associated with program file lib/ssl/src/tls_gen_connection.erl.

This issue affects OTP from OTP 17.0 before 29.0.3, 28.5.0.3 and 27.3.4.14 corresponding to ssl from 5.3.4 before 11.7.3, 11.6.0.3 and 11.2.12.10. TLS 1.3 is affected starting with OTP 22.0, when TLS 1.3 support was added.

Comment 1 Peter Lemenkov 2026-07-10 14:58:28 UTC

*** Bug 2496750 has been marked as a duplicate of this bug. ***

Comment 2 Peter Lemenkov 2026-07-10 16:26:09 UTC

Fixed in Fedora rawhide (f45) via erlang-27.3.4.14-1.fc45, which ships the upstream OTP fix (ssl-11.2.12.10, in OTP 27.3.4.14).

f43 and f44 remain on the OTP 26.x line, which did not receive an upstream fix for this issue, so a downstream backport is required. Backports for f43/f44 are prepared; updates will follow via Bodhi.

Comment 3 Fedora Update System 2026-07-10 17:12:21 UTC

FEDORA-2026-dcf80dc1ff (erlang-26.2.5.21-4.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-dcf80dc1ff

Comment 4 Fedora Update System 2026-07-10 17:12:36 UTC

FEDORA-2026-965be97ac0 (erlang-26.2.5.21-4.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-965be97ac0

Comment 5 Fedora Update System 2026-07-11 01:34:42 UTC

FEDORA-2026-dcf80dc1ff has been pushed to the Fedora 44 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-dcf80dc1ff`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-dcf80dc1ff

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 6 Fedora Update System 2026-07-11 01:47:51 UTC

FEDORA-2026-965be97ac0 has been pushed to the Fedora 43 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-965be97ac0`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-965be97ac0

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 7 Fedora Update System 2026-07-19 03:55:56 UTC

FEDORA-2026-965be97ac0 (erlang-26.2.5.21-4.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 8 Fedora Update System 2026-07-19 05:47:29 UTC

FEDORA-2026-dcf80dc1ff (erlang-26.2.5.21-4.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.