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no cvss —

CVE-2022-50731 json

crypto: akcipher - default implementation for setting a private key

published 2025-12-24 10 mo ago modified 2026-06-17 4 mo ago also EUVD-2022-55758

cvss
—
not scored
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 16%
public exploits
0
none known

Summary

In the Linux kernel, the following vulnerability has been resolved:

crypto: akcipher - default implementation for setting a private key

Changes from v1: * removed the default implementation from set_pub_key: it is assumed that an implementation must always have this callback defined as there are no use case for an algorithm, which doesn't need a public key

Many akcipher implementations (like ECDSA) support only signature verifications, so they don't have all callbacks defined.

Commit 78a0324f4a53 ("crypto: akcipher - default implementations for request callbacks") introduced default callbacks for sign/verify operations, which just return an error code.

However, these are not enough, because before calling sign the caller would likely call set_priv_key first on the instantiated transform (as the in-kernel testmgr does). This function does not have a default stub, so the kernel crashes, when trying to set a private key on an akcipher, which doesn't support signature generation.

I've noticed this, when trying to add a KAT vector for ECDSA signature to the testmgr.

With this patch the testmgr returns an error in dmesg (as it should) instead of crashing the kernel NULL ptr dereference.

Patch / fix

  • Linux Linux 5.4.220, 5.10.150, 5.15.75, 5.19.17, 6.0.3, 6.1
  • linux Debian 14, Debian 13, Debian 12 6.0.3-1

debian advisories DEBIAN-CVE-2022-50731

  • linux Ubuntu 20.04 LTS 5.4.0-139.156
  • linux Ubuntu 22.04 LTS 5.15.0-60.66
  • linux-aws Ubuntu 20.04 LTS 5.4.0-1096.104
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1030.34
  • linux-gcp Ubuntu 20.04 LTS 5.4.0-1100.109
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1029.36
  • linux-gke Ubuntu 22.04 LTS 5.15.0-1027.32
  • linux-ibm Ubuntu 20.04 LTS 5.4.0-1044.49

ubuntu advisories UBUNTU-CVE-2022-50731

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

  • kernel-64kb SLES 15 SP4-LTSS, SLE High Performance Computing 15 SP4-LTSS, SLE High Performance Computing 15 SP4-ESPOS 5.14.21-150400.24.194.1
  • kernel-syms SLES for SAP 15 SP4, SLES 15 SP4-LTSS, SLE High Performance Computing 15 SP4-LTSS +1 more 5.14.21-150400.24.194.1
  • kernel-source SLES for SAP 15 SP4, SLES 15 SP4-LTSS, SLE High Performance Computing 15 SP4-LTSS +1 more 5.14.21-150400.24.194.1
  • kernel-default SLES for SAP 15 SP4, SLES 15 SP4-LTSS, SLE Micro 5.4 +5 more 5.14.21-150400.24.194.1
  • kernel-obs-build SLES for SAP 15 SP4, SLES 15 SP4-LTSS, SLE High Performance Computing 15 SP4-LTSS +1 more 5.14.21-150400.24.194.1
  • kernel-default-base SLES for SAP 15 SP4, SLES 15 SP4-LTSS, SLE Micro 5.4 +3 more 5.14.21-150400.24.194.1.150400.24.98.3
  • kernel-rt SLE Micro 5.4, SLE Micro 5.3 5.14.21-150400.15.142.1
  • kernel-source-rt SLE Micro 5.4, SLE Micro 5.3 5.14.21-150400.15.142.1

suse advisories SUSE-SU-2026:0617-1SUSE-SU-2026:0411-1SUSE-SU-2026:0369-1SUSE-SU-2026:0350-1SUSE-SU-2026:0317-1SUSE-SU-2026:0263-1

Vendor advisories

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

red hat product security vex CVE-2022-50731 updated cvss 5.5

kernel: Linux kernel: Denial of Service in akcipher due to missing set_priv_key stub

  • Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more
    affected: no fix available “Fix deferred”
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 10 kernel
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-08).

Affected products

  • Linux Linux

Classification

Technology feeds

References

Sources

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