CVE-2026-59251
What it is
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 29.0.4, OTP 28.5.0.4 and OTP 27.3.4.15, corresponding to public_key from 1.15 before 1.21.4, 1.20.3.4 and 1.17.1.5.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of service disruption.
- Exploit odds
- 0.3% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.3% in the next 30 days (EPSS).
- Severity: 8.7 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.3% · EPSS, next 30 days
- Weakness
- CWE-770 · Allocation without limits
- Record status
- Analyzed
Affected
- Erlang erlang\/otp < 27.3.4.15
- Erlang erlang\/otp < 28.5.0.4
- Erlang erlang\/otp < 29.0.4
- Erlang erlang\/public Key < 1.17.1.5
- Erlang erlang\/public Key < 1.20.3.4
- Erlang erlang\/public Key < 1.21.4
Attack profile CVSS 4.0 · 8.7
- Attack vector
- Network
- Complexity
- Low
- Attack requirements
- None
- Privileges needed
- None
- User interaction
- None
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
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
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-59251.md and follow it. Check whether this project is affected by CVE-2026-59251. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://cna.erlef.org/cves/CVE-2026-59251.html
- https://github.com/erlang/otp/commit/f04c6bba38de1cf1b1836a7d9a9fbe239bd939e8
- https://github.com/erlang/otp/commit/f8580fc117098c08165f46c26fd0750c5cfb2a90
- https://github.com/erlang/otp/security/advisories/GHSA-622p-qfh6-c352
- https://osv.dev/vulnerability/EEF-CVE-2026-59251
References
- https://cna.erlef.org/cves/CVE-2026-59251.html
- https://github.com/erlang/otp/commit/f04c6bba38de1cf1b1836a7d9a9fbe239bd939e8
- https://github.com/erlang/otp/commit/f8580fc117098c08165f46c26fd0750c5cfb2a90
- https://github.com/erlang/otp/security/advisories/GHSA-622p-qfh6-c352
- https://osv.dev/vulnerability/EEF-CVE-2026-59251
- https://www.erlang.org/doc/system/versions.html#order-of-versions