Red Hat Security Advisory: libsoup3 security update
Affects Red Hat libsoup3Source GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 8.2 High.
Data as of 2 Nov 2026, 10:57 UTC
Thin evidence
One scorer or none| CNA (redhat) | CVSS 3.1 | 8.2 |
|---|
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 30% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 29 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Red Hat Enterprise Linux 10libsoup3 | Affected– | Fixed in– |
| Red Hat Enterprise Linux 10.0 Extended Update Supportlibsoup3 | Affected– | Fixed in– |
| Red Hat Enterprise Linux 6libsoup | Affected– | Fixed in– |
| Red Hat Enterprise Linux 7libsoup | Affected– | Fixed in– |
| Red Hat Enterprise Linux 8libsoup | Affected– | Fixed in– |
| Red Hat Enterprise Linux 9libsoup | Affected– | Fixed in– |
AI-suggested
Red Hat has released security updates for libsoup3 in Red Hat Enterprise Linux 10.0 Extended Update Support that address these heap buffer overflow vulnerabilities. Users should apply the provided updates as detailed in the Red Hat advisory (RHSA-2026:93583) to remediate these issues. For update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation steps are indicated by the vendor advisory.
Description
Multiple heap buffer overflow vulnerabilities have been identified in libsoup3, an HTTP library used in GNOME applications. These flaws involve uninitialized length in data-URI base64 decoding and various WebSocket processing stages, including Pong signal handling, message reassembly, receive-buffer growth, client-frame masking, and permessage-deflate buffer growth. Red Hat has issued an important security update addressing these issues in Red Hat Enterprise Linux 10.0 Extended Update Support.
References
- access.redhat.com/errata/RHSA-2026:93583 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2543224 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2543229 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2543231 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2543274 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2543285 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2543296 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_93583.json (opens in a new tab)