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Fencer Intel
high 7.5

CVE-2026-59251 json

Denial of service via exponential certificate policy tree growth in path validation

published 3mo ago modified 10h ago also EUVD-2026-49325 , GHSA-622p-qfh6-c352

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository erlang/otp. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 25%
public exploits
0
none known

Summary

Allocation of resources without limits in Erlang/OTP public_key certificate path validation allows a remote unauthenticated attacker to cause denial of service by sending a crafted X.509 certificate chain during the TLS handshake.

During RFC 5280 policy processing in public_key:pkix_path_validation/3, the certificate policy tree maintained by pubkey_policy_tree grows without an upper bound. When a certificate chain contains M policies per certificate and K certificates, the tree grows on the order of M^K nodes because pubkey_policy_tree:add_leaves/2 and pubkey_policy_tree:add_leaf_siblings/2 extend the tree per policy per certificate. A modest chain with many policies per certificate is enough to pin BEAM schedulers and exhaust the node's memory, taking down the entire VM. The attacker only needs to be able to present a certificate chain to the victim, which is the normal precondition for a TLS handshake, so exploitation succeeds against any incoming or outgoing TLS connection that validates the peer's chain (the default for SSL/TLS clients and mutual-TLS servers).

This is the same vulnerability class as OpenSSL's X509_verify_cert policy tree DoS.

This vulnerability is associated with program files lib/public_key/src/pubkey_policy_tree.erl and program routines pubkey_policy_tree:add_leaves/2 and pubkey_policy_tree:add_leaf_siblings/2.

This issue affects OTP from OTP 26.2 before OTP 27.3.4.15, OTP 28.5.0.4, and OTP 29.0.4, corresponding to public_key from 1.15 before 1.17.1.5, 1.20.3.4, and 1.21.4.

Patch / fix

  • Erlang OTP 1.17.1.5, 1.20.3.4, 1.21.4, 27.3.4.15, 28.5.0.4, 29.0.4
  • erlang Debian 13 1:27.3.4.1+dfsg-1+deb13u3
  • erlang Debian 14 1:29.0.4+dfsg-1

debian advisories DEBIAN-CVE-2026-59251

  • erlang Ubuntu 26.04 LTS 1:27.3.4.6+dfsg-1ubuntu0.1

ubuntu advisories UBUNTU-CVE-2026-59251

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

  • erlang27 hummingbird 1 27.3.4.15-0.1.hum1
  • erlang27-et hummingbird 1 27.3.4.15-0.1.hum1
  • erlang27-wx hummingbird 1 27.3.4.15-0.1.hum1
  • erlang27-ftp hummingbird 1 27.3.4.15-0.1.hum1
  • erlang27-ssh hummingbird 1 27.3.4.15-0.1.hum1
  • erlang27-ssl hummingbird 1 27.3.4.15-0.1.hum1
  • erlang27-asn1 hummingbird 1 27.3.4.15-0.1.hum1
  • erlang27-edoc hummingbird 1 27.3.4.15-0.1.hum1

red hat advisories RHSA-2026:47009

  • erlang26 SLES for SAP 15 SP6, SLES 15 SP6-LTSS, SLE Module for Server Applications 15 SP7 26.2.1-150300.7.28.1

suse advisories SUSE-SU-2026:3579-1

  • erlang openSUSE Tumbleweed 28.5.0.4-1.1
  • erlang27 openSUSE Tumbleweed 27.1.3-3.1

opensuse advisories openSUSE-SU-2026:11559-1openSUSE-SU-2026:11560-1

  • erlang Azure Linux 3.0 26.2.5.21-4

azure linux advisories AZL-94202

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

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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-2026-59251 updated cvss 7.5

Erlang/OTP: public_key: Erlang/OTP public_key: Denial of Service via crafted TLS certificate chains

  • Red Hat Hardened Images erlang27 27.3.4.15-0.1.hum1
    fixed: vendor fix RHSA-2026:47009

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
none
Automatable
yes
Technical impact
partial
Assessed
3mo ago

Exploit prediction

0.32% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 4.0 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L
CNA 4.0 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 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

  • Erlang OTP

Classification

Weakness
  • CWE-770 Allocation of Resources Without Limits or Throttling

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.

The maintainers of erlang/otp published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.