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Fencer Vulns
high 7.5

CVE-2026-43823 json

When initializing an RSA public key from DER or PEM bytes throws an error, the EVP_PKEY* is double-freed: first in the catch block, then in…

published 2026-07-23 3 mo ago modified 2026-10-24 15 d ago also EUVD-2026-48288

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 37%
public exploits
0
none known

Summary

When initializing an RSA public key from DER or PEM bytes throws an error, the EVP_PKEY* is double-freed: first in the catch block, then in the deinit. This can lead to a crash on future memory allocations. This double-free manifests when BoringSSL cannot decode the public key from the bytes provided. This vulnerability is addressed in swift-crypto version 4.5.1.

Patch / fix

  • Apple swift-crypto 4.5.1
  • swift-lang hummingbird 1 6.3.3-0.1.1.hum1
  • swift-lang-runtime hummingbird 1 6.3.3-0.1.1.hum1
  • nodejs24 hummingbird 1 24.18.0-0.5.hum1
  • nodejs24-bin hummingbird 1 24.18.0-0.5.hum1
  • nodejs24-npm hummingbird 1 11.16.0-1.24.18.0.0.5.hum1
  • nodejs24-libs hummingbird 1 24.18.0-0.5.hum1
  • nodejs24-npm-bin hummingbird 1 24.18.0-0.5.hum1
  • nodejs24-full-i18n hummingbird 1 24.18.0-0.5.hum1

red hat advisories RHSA-2026:45785RHSA-2026:45784

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-2026-43823 updated cvss 6.2

swift-crypto: swift-crypto: Denial of Service due to double-free during RSA public key initialization

  • Red Hat Hardened Images nodejs24 24.18.0-0.5.hum1, swift-lang 6.3.3-0.1.1.hum1, nodejs24-bin 24.18.0-0.5.hum1, nodejs24-libs 24.18.0-0.5.hum1, nodejs24-npm-bin 24.18.0-0.5.hum1, nodejs24-full-i18n 24.18.0-0.5.hum1, +2 more
    fixed: vendor fix RHSA-2026:45784
  • Red Hat Hardened Images v8-13.6-devel 13.6.233.17-1.24.18.0.0.5.hum1
    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

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/apple/swift-crypto/security/advisories/GHSA-8q93-f6xh-4f6f referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CISA ADP 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Apple swift-crypto

Classification

Weakness

References

Sources

Fencer Vulns 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.