{"id":"CVE-2026-42507","aliases":["GO-2026-5039","BIT-golang-2026-42507"],"title":"Arbitrary inputs are included in errors without any escaping in net/textproto","summary":"Arbitrary inputs are included in errors without any escaping in net/textproto","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","vendor":"stdlib","product":"stdlib","ecosystem":"go","affected":["stdlib >= 1.26.0-0, < 1.26.4"],"patched":["stdlib 1.26.4"],"published":"2026-06-02","updated":"2026-10-03","sourceUpdated":"2026-10-03T10:41:52.575378248Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GO-2026-5039","references":[{"url":"https://go.dev/issue/79346"},{"url":"https://go.dev/cl/777060"},{"url":"https://groups.google.com/g/golang-announce/c/tKs3rmcBcKw"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42507.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-42507"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2484205"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-42507"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42507"},{"url":"https://pkg.go.dev/vuln/GO-2026-5039"},{"url":"https://access.redhat.com/errata/RHSA-2026:49702"},{"url":"https://access.redhat.com/errata/RHSA-2026:29980"},{"url":"https://access.redhat.com/errata/RHSA-2026:38995"},{"url":"https://access.redhat.com/errata/RHSA-2026:61253"},{"url":"https://access.redhat.com/errata/RHSA-2026:57649"},{"url":"https://access.redhat.com/errata/RHSA-2026:49712"},{"url":"https://access.redhat.com/errata/RHSA-2026:66364"},{"url":"https://access.redhat.com/errata/RHSA-2026:29981"},{"url":"https://access.redhat.com/errata/RHSA-2026:23262"},{"url":"https://access.redhat.com/errata/RHSA-2026:23264"},{"url":"https://access.redhat.com/errata/RHSA-2026:50205"},{"url":"https://access.redhat.com/errata/RHSA-2026:33612"},{"url":"https://access.redhat.com/errata/RHSA-2026:57194"},{"url":"https://access.redhat.com/errata/RHSA-2026:59556"}],"tags":["osv","go","csaf","vex","red-hat"],"epss":0.0037,"epssPercentile":0.30793,"cvssSource":"vendor","cwe":["CWE-117"],"ingestedAt":"2026-07-31T19:10:07.997Z","slug":"CVE-2026-42507","body":"## Overview\n\nWhen returning errors, functions in the net/textproto package would include its input as part of the error. This might allow an attacker to inject misleading content to errors that are printed or logged.\n\n## Affected packages\n\n- `stdlib >= 1.26.0-0, < 1.26.4`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `stdlib 1.26.4`\n\n## Vendor advisories\n\n- **RHSA-2026:49702** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · released 2026-08-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:49702)\n- **RHSA-2026:29980** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10) · released 2026-06-25 · [advisory](https://access.redhat.com/errata/RHSA-2026:29980)\n- **RHSA-2026:38995** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8) · released 2026-07-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:38995)\n- **RHSA-2026:61253** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.2) · released 2026-08-31 · [advisory](https://access.redhat.com/errata/RHSA-2026:61253)\n- **RHSA-2026:57649** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.4) · released 2026-08-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:57649)\n- **RHSA-2026:49712** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.6) · released 2026-08-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:49712)\n- **RHSA-2026:66364** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9) · released 2026-09-10 · [advisory](https://access.redhat.com/errata/RHSA-2026:66364)\n- **RHSA-2026:29981** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9) · released 2026-06-25 · [advisory](https://access.redhat.com/errata/RHSA-2026:29981)\n- **RHSA-2026:23262** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-06-04 · [advisory](https://access.redhat.com/errata/RHSA-2026:23262)\n- **RHSA-2026:23264** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-06-04 · [advisory](https://access.redhat.com/errata/RHSA-2026:23264)\n- **RHSA-2026:50205** · Red Hat · fixed in: Red Hat OpenShift distributed tracing 3.10.2 · released 2026-08-04 · [advisory](https://access.redhat.com/errata/RHSA-2026:50205)\n- **Red Hat VEX** · Moderate · affected: Assisted Installer for Red Hat OpenShift Container Platform 2, Builds for Red Hat OpenShift, cert-manager Operator for Red Hat OpenShift, Compliance Operator, Confidential Compute Attestation, Cryostat 4, … · no fix planned: Assisted Installer for Red Hat OpenShift Container Platform 2, Builds for Red Hat OpenShift, cert-manager Operator for Red Hat OpenShift, Compliance Operator, … · updated 2026-10-02 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42507.json)\n- **RHSA-2026:33612** · Red Hat · fixed in: Red Hat OpenShift distributed tracing 3.10.2 · released 2026-06-30 · [advisory](https://access.redhat.com/errata/RHSA-2026:33612)","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":5204,"id":"CVE-2026-42507","ts":1788887253539,"field":"cvss","old":null,"new":"5.3"},{"seq":5203,"id":"CVE-2026-42507","ts":1788887253539,"field":"severity","old":"none","new":"medium"},{"seq":4087,"id":"CVE-2026-42507","ts":1788886369391,"field":"cvss","old":"5.3","new":null},{"seq":4086,"id":"CVE-2026-42507","ts":1788886369391,"field":"severity","old":"medium","new":"none"},{"seq":3165,"id":"CVE-2026-42507","ts":1788883133162,"field":"cvss","old":null,"new":"5.3"},{"seq":3164,"id":"CVE-2026-42507","ts":1788883133162,"field":"severity","old":"none","new":"medium"}]}