Vulnerability in Juniper TCP proxy plugin of (CVE-2026-57023)
Summary
Vulnerability in Juniper TCP proxy plugin of (CVE-2026-57023). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
An Improper Validation of Specified Quantity in Input vulnerability in the TCP proxy plugin of Juniper Networks Junos OS on MX Series with SPC3, and SRX Series allows an unauthenticated, network-based attacker to cause a complete Denial of Service (DoS).
When TCP proxy is engaged in a flow session, to support ALGs, Advanced Anti-Malware, ICAP or UTM, a TCP packet with specifically malformed TCP header will cause flow processing daemon (flowd) to crash and restart. This causes a complete service outage until the system has automatically recovered.
This issue affects Junos OS on MX with SPC3, and SRX Series:
- 23.4 versions before 23.4R2-S7,
- 24.2 versions before 24.2R2-S4,
- 24.4 versions before 24.4R2-S3,
- 25.2 versions before 25.2R2.
This issue does not affect releases before 23.4R1.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-57023 has been found in Juniper TCP proxy plugin of.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Juniper TCP proxy plugin of CVE-2026-57023" on the vendor's site.
CVE-2026-57023 (Juniper TCP proxy plugin of) — CWE-1284 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-1284) exists in Juniper TCP proxy plugin of.
Check the vendor advisory for the affected versions of Juniper TCP proxy plugin of.
Severity: High (CVSS 7.5/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Juniper TCP proxy plugin of を使っているサービスとバージョンを洗い出す。
-
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- patch sirt@juniper.net
- web nvd.nist.gov
- web github.com