CVE-2017-6542

Exp

The ssh_agent_channel_data function in PuTTY before 0.68 allows remote attackers to have unspecified impact via a large length value in an agent protocol message and leveraging the ability to connect to the Unix-domain socket representing the forwarded agent connection, which trigger a buffer overflow.

Published: 2017-03-27 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-6542 is rated High Exploit Risk (83.3/100): CVSS Critical severity, with high exploitation likelihood (EPSS 21.82%, 97th percentile). 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-2017-6542

EDB-ID Source Kind Published Link
42137 exploit_db edb 2017-06-07 Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2017-6542

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 2026-06-15 30.63% 21.82% -8.82%
2 2026-05-29 23.01% 30.63% +7.62%
3 2026-05-27 — 23.01% —

Full EPSS history (15 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-6542

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.0 CRITICAL
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H 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:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2017-6542

OS Trackers for CVE-2017-6542

vendor priority summary link
debian not yet assigned CVE-2017-6542 not yet assigned priority: Debian including 1 source packages (putty), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2017-6542
gentoo normal CVE-2017-6542: 2 GLSA(s) (201703-03, 201706-09), 2 atom(s) (net-ftp/filezilla, net-misc/putty); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2017-6542
ubuntu medium CVE-2017-6542 medium priority: Ubuntu including 1 source packages (putty), 10 status rows across 10 suites (artful, bionic, cosmic, disco, precise, trusty, upstream, xenial, yakkety, zesty): ignored 4, not-affected 3, released 2, DNE 1. https://ubuntu.com/security/CVE-2017-6542

Affected software / configurations for CVE-2017-6542

Vendor Product Version Raw CPE
putty putty <= 0.67 cpe:2.3:a:putty:putty:*:*:*:*:*:*:*:*
opensuse leap 42.2 cpe:2.3:o:opensuse:leap:42.2:*:*:*:*:*:*:*
opensuse_project leap 42.1 cpe:2.3:o:opensuse_project:leap:42.1:*:*:*:*:*:*:*

References for CVE-2017-6542

cvelogic Threat Intelligence