CVE-2026-33487 | goxmldsig has validateSignature Loop Variable Capture Signature Bypass

Exp

goxmlsig provides XML Digital Signatures implemented in Go. Prior to version 1.6.0, the `validateSignature` function in `validate.go` goes through the references in the `SignedInfo` block to find one that matches the signed element's ID. In Go versions before 1.22, or when `go.mod` uses an older version, there is a loop variable capture issue. The code takes the address of the loop variable `_ref` instead of its value. As a result, if more than one reference matches the ID or if the loop logic is incorrect, the `ref` pointer will always end up pointing to the last element in the `SignedInfo.References` slice after the loop. goxmlsig version 1.6.0 contains a patch.

Published: 2026-03-26 Last update: 2026-04-20 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-33487 is rated Exploit Available (50/100): CVSS High severity, with low exploitation likelihood (EPSS 0.02%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-33487

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-33487

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-27 — 0.02% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-33487

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-33487

GitHub Security Advisory for CVE-2026-33487

GHSA-479m-364c-43vc · Severity: high · Ecosystem: go — validateSignature Loop Variable Capture Signature Bypass in goxmldsig

OS Trackers for CVE-2026-33487

vendor priority summary link
redhat high — https://access.redhat.com/security/cve/CVE-2026-33487

Affected software / configurations for CVE-2026-33487

Vendor Product Version Raw CPE
goxmldsig_project goxmldsig < 1.6.0 cpe:2.3:a:goxmldsig_project:goxmldsig:*:*:*:*:*:*:*:*

References for CVE-2026-33487

cvelogic Threat Intelligence