CVE-2026-70409

MEDIUM CVSS 4.0: 6.3 EPSS 0.42%
Updated Sep 08, 2026
Erlang
Parameter Value
CVSS 6.3 (MEDIUM)
Affected Versions 17.0 — 29.0.6
Fixed In 27.3.4.17
Type CWE-1284
Vendor Erlang
Public PoC No

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.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
Low
Partial disruption

CVSS Vector v4.0

Weakness Type (CWE)

Vulnerable Products 3

Configuration From (including) Up to (excluding)
Erlang Erlang\/Otp
cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
17.0 27.3.4.17
Erlang Erlang\/Otp
cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
28.0 28.5.0.6
Erlang Erlang\/Otp
cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
29.0 29.0.6