CVE-2017-6891

Two errors in the "asn1_find_node()" function (lib/parser_aux.c) within GnuTLS libtasn1 version 4.10 can be exploited to cause a stacked-based buffer overflow by tricking a user into processing a specially crafted assignments file via the e.g. asn1Coding utility.

Published: 2017-05-22 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-6891 is rated Moderate Risk (64.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.59%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2017-6891

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 2026-05-29 1.18% 1.59% +0.41%
2 2026-03-17 1.01% 1.18% +0.17%
3 2026-02-09 — 1.01% —

Full EPSS history (26 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-6891

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/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:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
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.
 2.8 5.9 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/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:M)
Exploitation needs some favorable conditions, but not exceptional ones.
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.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2017-6891

OS Trackers for CVE-2017-6891

vendor priority summary link
debian not yet assigned CVE-2017-6891 not yet assigned priority: Debian including 1 source packages (libtasn1-6), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2017-6891
gentoo normal CVE-2017-6891: 1 GLSA(s) (201710-11), 1 atom(s) (dev-libs/libtasn1); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2017-6891
redhat low — https://access.redhat.com/security/cve/CVE-2017-6891
suse medium CVE-2017-6891 severity moderate: SUSE including 40 source package names (24.4:libtasn1-4.9-3.10.1, 24.4:libtasn1-6-4.9-3.10.1, …), 244 product×package rows across 66 product lines (Container caasp/v4/nginx-ingress-controller, Container suse/ltss/sle12.5/sles12sp5, … (66 product lines)): Known Not Affected 129, Fixed 115. https://www.suse.com/security/cve/CVE-2017-6891/
ubuntu medium CVE-2017-6891 medium priority: Ubuntu including 2 source packages (libtasn1-3, libtasn1-6), 10 status rows across 5 suites (trusty, upstream, xenial, yakkety, zesty): released 5, DNE 4, needs-triage 1. https://ubuntu.com/security/CVE-2017-6891

Affected software / configurations for CVE-2017-6891

Vendor Product Version Raw CPE
gnu libtasn1 4.10 cpe:2.3:a:gnu:libtasn1:4.10:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
apache bookkeeper 4.12.1 cpe:2.3:a:apache:bookkeeper:4.12.1:*:*:*:*:*:*:*

References for CVE-2017-6891

URL Tags
http://git.savannah.gnu.org/gitweb/?p=libtasn1.git%3Ba=commit%3Bh=5520704d075802df25ce4ffccc010ba1641bd484
http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00018.html Broken Link
http://www.debian.org/security/2017/dsa-3861 Third Party Advisory
http://www.securityfocus.com/bid/98641 Third Party Advisory VDB Entry
http://www.securitytracker.com/id/1038619 Third Party Advisory VDB Entry
https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
https://secuniaresearch.flexerasoftware.com/advisories/76125/ Permissions Required
https://secuniaresearch.flexerasoftware.com/secunia_research/2017-11/ Patch Third Party Advisory
https://security.gentoo.org/glsa/201710-11 Third Party Advisory
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