Unauthenticated application crash via truncated Telnet command
Published Jun 29, 2026 · Updated Jun 29, 2026
Heap out-of-bounds read in PcapPlusPlus 25.05 allows remote attackers to crash packet-processing applications with truncated Telnet commands. TelnetLayer::getCommandLength reports three bytes for a WILL, WONT, DO, or DONT command even when only two remain, so getSubCommand later reads pos[2] beyond the packet buffer. The consuming application must parse attacker-controlled Telnet traffic and invoke the option accessor; the demonstrated consequence is an AddressSanitizer-detected crash.
Summary
What happened
Heap out-of-bounds read in PcapPlusPlus 25.05 allows remote attackers to crash packet-processing applications with truncated Telnet commands. TelnetLayer::getCommandLength reports three bytes for a WILL, WONT, DO, or DONT command even when only two remain, so getSubCommand later reads pos[2] beyond the packet buffer. The consuming application must parse attacker-controlled Telnet traffic and invoke the option accessor; the demonstrated consequence is an AddressSanitizer-detected crash.
The record
- CVE
- CVE-2026-13589
- Published
- Jun 29, 2026
- Updated
- Jun 29, 2026
- Vendor
- seladb
- Product
- PcapPlusPlus
- Classifications
- T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 29, 2026CVE publishedPublication date reported by the CVE source.
- Jun 29, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=25.05
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- TelnetLayer getSubCommand proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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