CVE-2025-30211: erlang otp · Excessive Memory Allocation
Affects erlang otpSource CVE Database V5
Not known to be exploited · CVSS 7.5 High · fixed in 27.3.1 : patch erlang otp soon.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 40% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 27.3.1, 26.2.5.10, 25.3.2.19
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 28 Mar 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
Upgrade erlang/otp to 27.3.1, 26.2.5.10 or 25.3.2.19.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
GitHuberlang/otppkg:github/erlang/otpOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
To mitigate CVE-2025-30211, organizations should prioritize upgrading Erlang/OTP to versions 27.3.1, 26.2.5.10, or 25.3.2.19 where the vulnerability is patched. If immediate upgrade is not feasible, apply configuration workarounds by disabling the 'parallel_login' option to prevent concurrent session establishment that exacerbates memory usage. Additionally, reduce the 'max_sessions' parameter to limit the number of simultaneous sessions, thereby controlling resource allocation. Network-level protections such as rate limiting and deep packet inspection can help detect and block malformed KEX init messages. Monitoring memory usage patterns and setting alerts for abnormal spikes can provide early warning of exploitation attempts. Implementing strict input validation and anomaly detection on key exchange messages at the application or network gateway level can further reduce risk. Regularly review Erlang/OTP deployments and maintain updated inventories to ensure timely patching and configuration management.
Description
Erlang/OTP is a set of libraries for the Erlang programming language. Prior to versions OTP-27.3.1, 26.2.5.10, and 25.3.2.19, a maliciously formed KEX init message can result with high memory usage. Implementation does not verify RFC specified limits on algorithm names (64 characters) provided in KEX init message. Big KEX init packet may lead to inefficient processing of the error data. As a result, large amount of memory will be allocated for processing malicious data. Versions OTP-27.3.1, OTP-26.2.5.10, and OTP-25.3.2.19 fix the issue. Some workarounds are available. One may set option `parallel_login` to `false` and/or reduce the `max_sessions` option.