Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
🛡️
CISA KEV · ACTIVELY EXPLOITED
HIGH severity

CVE-2021-25487

HIGH

CVE-2021-25487 is a high-severity (CVSS 7.3) Out-of-bounds Read vulnerability. It is in CISA's Known Exploited Vulnerabilities catalog (added 2023-06-29) — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.

Lack of boundary checking of a buffer in set_skb_priv() of modem interface driver prior to SMR Oct-2021 Release 1 allows OOB read and it results in arbitrary code execution by dereference…

Published
Updated
Affected
1 product
Patched
See advisory
Exploits
2 known
Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, CISA KEV, FIRST.org (EPSS)

Exploitation Status

Actively exploited in the wild

  • Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2023-06-29. Federal agencies were required to remediate by 2023-07-20.
  • A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2021-25487.

EPSS Exploitation Probability

via FIRST.org ↗
0.6%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs50th percentile — riskier than 50% of all scored CVEsHighest risk
0.00%1.10%2.20%3.30%2.4%0.6%Apr 26Jul 26Oct 26

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

How urgent is this, really

CVE-2021-25487 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 395,308 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Description

Lack of boundary checking of a buffer in set_skb_priv() of modem interface driver prior to SMR Oct-2021 Release 1 allows OOB read and it results in arbitrary code execution by dereference of invalid function pointer.

Affected Products

1 product · 28 configurations
OS
androidsamsung
4 versions
8.19.010.011.0
Exploits & PoCs
2

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Lack of boundary checking of a buffer in set_skb_priv() of modem interfa…

security.samsungmobile.comGoogle-sheetJul 2021

Lack of boundary checking of a buffer in set_skb_priv() of modem interfa…

cisa.govCISAJun 2023

Detection & mitigation playbook

Vulnerability

  1. Detect

    Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).

  2. Remediation status

    No fixed release is recorded for CVE-2021-25487 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.

  3. Mitigate without a patch

    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.

Frequently Asked Questions

Lack of boundary checking of a buffer in set_skb_priv() of modem interface driver prior to SMR Oct-2021 Release 1 allows OOB read and it results in arbitrary code execution by dereference of invalid function pointer.
O3 Security · Impact-Aware SCA

Is CVE-2021-25487 in your dependencies?

Find it across , including transitive dependencies.

Scan my dependencies How O3 SCA works
CVE-2021-25487: Memory Corruption (High 7.3, KEV)