VulnerabilityModified

CVE-2026-28810

Generation of Predictable Numbers or Identifiers vulnerability in Erlang/OTP kernel (inet_res, inet_db modules) allows DNS Cache Poisoning.

MEDIUM 6.3EPSS 0.27%

Does this matter?

Lower severity and a low EPSS score (0.27%). Track it; it rarely justifies an emergency change on its own.

Description

Generation of Predictable Numbers or Identifiers vulnerability in Erlang/OTP kernel (inet_res, inet_db modules) allows DNS Cache Poisoning. The built-in DNS resolver (inet_res) uses a sequential, process-global 16-bit transaction ID for UDP queries and does not implement source port randomization. Response validation relies almost entirely on this ID, making DNS cache poisoning practical for an attacker who can observe one query or predict the next ID. This conflicts with RFC 5452 recommendations for mitigating forged DNS answers. inet_res is intended for use in trusted network environments and with trusted recursive resolvers. Earlier documentation did not clearly state this deployment assumption, which could lead users to deploy the resolver in environments where spoofed DNS responses are possible. This vulnerability is associated with program files lib/kernel/src/inet_db.erl and lib/kernel/src/inet_res.erl. This issue affects OTP from OTP 17.0 before OTP 28.4.2, OTP 27.3.4.10 and OTP 26.2.5.19, corresponding to kernel from 3.0 before 10.6.2, 10.2.7.4 and 9.2.4.11.

CVSS 4.0: 6.3 MEDIUMCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.27% probability · 19th percentile
CISA KEV: Not listed
Weakness: CWE-340
Affected: erlang/erlang\/otp
Source: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db

References

https://cna.erlef.org/cves/CVE-2026-28810.htmlThird Party Advisory
https://github.com/erlang/otp/commit/36f23c9d2cc54afe83671dd7343596d7972839a5Patch
https://github.com/erlang/otp/commit/b057a9d995017b1be50d6dc02edd52382f3231b8Patch
https://github.com/erlang/otp/commit/dd15e8eb03548c5e55e9915f0e91389ec6bad9fdPatch
https://github.com/erlang/otp/security/advisories/GHSA-v884-5jg5-whj8Vendor Advisory
https://osv.dev/vulnerability/EEF-CVE-2026-28810Third Party Advisory
https://www.erlang.org/doc/system/versions.html#order-of-versionsRelease Notes

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.