CVSS 4.0
6.3 mediumCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:NCVE-2026-123610
Medium (6.3) in rustls rustls. EPSS 0.2% estimated probability of exploitation activity in the next 30 days. Fixed in rustls 0.23.46, 0.24.0-dev.2.
On this page
rustls before 0.23.46 contains an uncontrolled memory allocation flaw in its optional Brotli certificate decompression, which limits decompressed output size but accepts an input-selected large history window. Malicious peers can send a certificate with a five-byte Brotli header requesting up to 1 GiB before authentication, aborting Brotli-enabled clients or client-authenticating servers whose allocator cannot satisfy the request.
Severity
CVSS 3.1
3.7 lowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 6th percentile. Scored 2026-11-10. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-09. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-770 Allocation of Resources Without Limits or Throttling
- Published
- Modified
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Explain CVE-2026-123610 for an engineer deciding whether to act. Use https://cve.bz/api/public/cves/CVE-2026-123610?via=ask-ai-copy and https://cve.bz/cve/CVE-2026-123610?via=ask-ai-copy as the source of truth: what is affected and which versions fix it, whether it is in CISA KEV, public exploits, and its EPSS (an internet-wide 30-day estimate of exploitation activity, not a forecast for my systems). If they give no fixed versions, use the CVE record https://cveawg.mitre.org/api/cve/CVE-2026-123610 or the vendor advisory, not third-party mirrors. Tell me how to check whether I am affected and how to verify a fix. Cite the sources and say where they are uncertain.Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this CVE's id and public links.
Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| rustls | before 0.23.46 |
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-h2v8-394m-p7vv | crates.io | rustls | <0.23.46 | 0.23.46 |
| GHSA-h2v8-394m-p7vv | crates.io | rustls | >=0.24.0-dev.1 <0.24.0-dev.2 | 0.24.0-dev.2 |
| RUSTSEC-2026-0348 | crates.io | rustls | >=0.23.9 <0.23.46 | 0.23.46 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12, 13, 14 | rust-rustls | no fix listed | DEBIAN-CVE-2026-123610 |
| Ubuntu | 24.04:LTS, 26.04:LTS, 26.10 | rust-rustls | no fix listed | UBUNTU-CVE-2026-123610 |
From the distributions' data via OSV.dev: the Debian Security Tracker; Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian · Ubuntu.
Attack patterns (CAPEC)
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits. More on the page of CWE-770 (20).