Skip to content
Fencer Intel
medium 5.5

CVE-2021-39633 json

In gre_handle_offloads of ip_gre.c, there is a possible page fault due to an invalid memory access.

published 4y ago modified 4mo ago also EUVD-2021-25990

cvss
5.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 8%
public exploits
0
none known

Summary

In gre_handle_offloads of ip_gre.c, there is a possible page fault due to an invalid memory access. This could lead to local information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-150694665References: Upstream kernel

Patch / fix

  • linux Debian 14, Debian 13, Debian 12 5.14.6-1

debian advisories DEBIAN-CVE-2021-39633

  • linux Ubuntu 18.04 LTS 4.15.0-162.170
  • linux Ubuntu 20.04 LTS 5.4.0-90.101
  • linux-aws Ubuntu 18.04 LTS 4.15.0-1115.122
  • linux-aws Ubuntu 20.04 LTS 5.4.0-1059.62
  • linux-gcp Ubuntu 20.04 LTS 5.4.0-1057.61
  • linux-gke Ubuntu 20.04 LTS 5.4.0-1055.58
  • linux-ibm Ubuntu 20.04 LTS 5.4.0-1007.8
  • linux-kvm Ubuntu 18.04 LTS 4.15.0-1102.104

ubuntu advisories UBUNTU-CVE-2021-39633

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Is CVE-2021-39633 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-24-074-07 updated cvss 5.5

Siemens SIMATIC

  • Siemens SIMATIC RF160B (6GT2003-0FA00) <V2.2
    affected: mitigation “Siemens has released a new version (V2.2) for SIMATIC RF160B and recommends to update to the latest version.” siemens.com

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

Exploit prediction

0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD 2.0 2.1 AV:L/AC:L/Au:N/C:P/I:N/A:N

Affected products

  • n/a Android

Classification

Weakness
  • CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.