CVE-2026-70409: medium-severity vulnerability in Erlang OTP
eldap does not bound the port component of a referral URL before integer conversion
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.3epss 0.6%
Improper Validation of Specified Quantity in Input vulnerability in Erlang/OTP eldap allows a malicious or compromised LDAP server to degrade availability by returning a referral URL whose port component is a very long run of digits.
eldap:parse_port/2 passes the port substring straight to list_to_integer/1 with no length bound. The surrounding try ... catch only rejects a value that fails to parse, so a syntactically valid port of up to roughly 1.26 million digits converts successfully and costs the caller hundreds of milliseconds of arbitrary-precision arithmetic per referral. The conversion function itself is documented to accept integers of any size, so bounding the input is the caller's responsibility. Reaching the flaw requires the application to pass a server-supplied referral to eldap:parse_ldap_url/1, which eldap never calls itself: referral strings are returned to the caller unparsed.
This issue affects OTP from OTP 17.0 before OTP 27.3.4.17, from OTP 28.0 before OTP 28.5.0.6, and from OTP 29.0 before OTP 29.0.6, corresponding to eldap from 1.0.3 before 1.2.14.2, from 1.2.15 before 1.2.16.1, and from 1.3 before 1.3.1.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Affected products
Erlang · OTPRelated CVEs — Erlang OTP
In the same product, most dangerous first.
CVE-2026-66835HIGHhttpd mod_auth directory protection bypassed by a doubled slash in the request pathEPSS 1.0%CVE-2026-69664HIGHhttpd parks a request worker indefinitely on a malformed chunk size sent after the headersEPSS 0.9%CVE-2026-73270HIGHhttpd mod_auth directory protection bypassed by request path casing on case-insensitive filesystemsEPSS 0.9%CVE-2026-70399HIGHhttpd does not enforce the documented default max_clients connection limitEPSS 0.9%CVE-2026-75538HIGHA Signed Length Overflow in Erlang/OTP's inet TCP Driver Overflows the Receive Buffer Into BEAM VM Memory From an Unauthenticated PeerEPSS 0.9%CVE-2026-59250HIGHMegaco flex scanner buffer overflow via oversized property parm nameEPSS 0.8%
References
https://cna.erlef.org/cves/CVE-2026-70409.htmlhttps://github.com/erlang/otp/commit/aba0fe8c2d700bf4ac94607cf7f00e53bbe4042dhttps://github.com/erlang/otp/commit/e3be1cfe9f6cedd0cd20d9905e05601dfb31c8aahttps://github.com/erlang/otp/security/advisories/GHSA-9vgh-c8cm-m9p4https://osv.dev/vulnerability/EEF-CVE-2026-70409https://www.erlang.org/doc/system/versions.html#order-of-versions