How severe is CVE-2025-55159?

No CVSS score has been assigned to CVE-2025-55159 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2025-55159?

CVE-2025-55159 affects the following packages: slab (crates.io). Ecosystems affected: crates.io.

How do I fix CVE-2025-55159?

Update slab to 0.4.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-55159 is resolved across your whole dependency graph.

How do I detect CVE-2025-55159 in my crates.io dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for slab, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2025-55159 if there is no patch (or I can't update yet)?

Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.

Is CVE-2025-55159 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-55159 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-55159?

CVE-2025-55159 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 8th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2025-55159?

CVE-2025-55159 is classified as Buffer Overflow (CWE-119). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2025-55159 published, and has it been updated?

CVE-2025-55159 was published on August 11, 2025 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2025-55159: slab — Fixed in 0.4.11

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2025-55159.

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs8th percentile — riskier than 8% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

🦀slab

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.

Description

slab is a pre-allocated storage for a uniform data type. In version 0.4.10, the get_disjoint_mut method incorrectly checked if indices were within the slab's capacity instead of its length, allowing access to uninitialized memory. This could lead to undefined behavior or potential crashes. This has been fixed in slab 0.4.11. A workaround for this issue involves to avoid using get_disjoint_mut with indices that might be beyond the slab's actual length.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`slab`	≥ 0.4.10&&< 0.4.11	0.4.11`cargo update -p slab --precise 0.4.11`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for slab, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update slab to 0.4.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-55159 is resolved across your whole dependency graph.
Workarounds
Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

Workaround published by Red Hat

To mitigate this flaw avoid using get_disjoint_mut with indices that might be beyond the slab's actual length

Source: Red Hat security advisory for CVE-2025-55159 (CC BY 4.0)

Frequently Asked Questions

slab is a pre-allocated storage for a uniform data type. In version 0.4.10, the get_disjoint_mut method incorrectly checked if indices were within the slab's capacity instead of its length, allowing access to uninitialized memory. This could lead to undefined behavior or potential crashes. This has been fixed in slab 0.4.11. A workaround for this issue involves to avoid using get_disjoint_mut with indices that might be beyond the slab's actual length.

O3 Security · Impact-Aware SCA

Is CVE-2025-55159 in your dependencies?

Find it across crates.io, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVE-2025-55159 — slab