CVE-2026-116135

NONE
Published: 2026-10-28
Modified: 2026-10-29
Enriched via mock
Tenable Plugin

Checking the public Tenable catalog…

AI Threat Summary

CVE-2026-116135 is a moderate vulnerability affecting the target software. Threat hunters should monitor for exploit attempts and apply vendor patches immediately.

Description

HTTP::Body versions before 1.23_01 for Perl drop mixed-case percent escapes from urlencoded form fields instead of decoding them. The decode table holds only the all-lowercase and all-uppercase spelling of each hex pair, while the escape pattern matches either case. An escape such as %aB finds no entry and is replaced with nothing, joining the bytes on either side. Hex digits in percent escapes are case-insensitive, and conforming decoders return the byte. A remote attacker can send a field name or value that a conforming decoder in front of the application reads differently, so that pass%aBword reaches the application as password.

Attack Chain
1
Reconnaissance

Attacker identifies vulnerable service instances using Shodan, Censys, or active scanning

2
Initial Access

Attacker crafts malicious payload exploiting CVE-2026-116135 to achieve remote code execution

3
Execution

Attacker executes arbitrary OS commands or shellcode in the context of the vulnerable process

4
Persistence

Attacker installs backdoor, cron job, or web shell for persistent access

5
Lateral Movement

Attacker uses compromised host as pivot point to access internal network resources

MITRE ATT&CK Techniques
T1190 Exploit Public-Facing Application
Initial Access

Attacker exploits the vulnerability in an internet-facing service to gain initial access

T1059 Command and Scripting Interpreter
Execution

Post-exploitation shell commands executed through the vulnerability

T1105 Ingress Tool Transfer
Command and Control

Attacker downloads malware or tools after gaining code execution

Indicators of Compromise
Type Value Description
user_agent Mozilla/5.0 (compatible; exploit/1.0) Generic exploit scanner user agent pattern
url /api/vuln-endpoint?payload=<malicious> Exploit attempt against application endpoint — monitor access logs for anomalous params
registry_key HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\backdoor Persistence mechanism after successful RCE
Remediation
1. Apply vendor-supplied security patches immediately. 2. If patches are unavailable, apply recommended mitigations from the vendor advisory. 3. Enable WAF rules or IDS signatures to detect exploitation attempts. 4. Monitor logs for indicators of compromise listed above. 5. Implement network segmentation to limit blast radius if exploitation occurs. 6. Subscribe to vendor security advisories for this product.