Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2017-15721

24
FAUCET Score

CVE-2017-15721 describes a NULL pointer dereference vulnerability in Irssi versions prior to 1.0.5, triggered by malformed DCC CTCP messages. This flaw carries a CVSS v3 score of 7.5 (High), indicating a network-exploitable vulnerability with low attack complexity that can lead to a denial of service. While no active exploitation, public exploit code, or significant community discussion has been observed, the vulnerability could still impact affected Debian and Irssi installations.

Impacted Technologies

VendorProductVersion(s)CPE
<= 1.0.4CPE matchmatch criteria
cpe:2.3:a:irssi:irssi:*:*:*:*:*:*:*:*
7.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*
8.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
9.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.0

7.5HIGH

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
Exploitability Score
3.9
Impact Score
3.6
CvssVersion
3.0

Exploit Intelligence

EPSS Score
2.37%
Probability of exploitation in next 30 days
EPSS Percentile
82.1%
Percentile rank of EPSS score among Peer Group
As of 2026-07-28
Model: v2026.06.15
This CVE's current EPSS score of 0.0237 is in the 68th percentile among its peer group of 51,553 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Vendor Patches (2)

redhatend of lifevia redhat_api
Product: Red Hat Enterprise Linux 6Fixed in: irssi
redhatend of lifevia redhat_api
Product: Red Hat Enterprise Linux 7Fixed in: irssi

Vendor Advisories (1)

redhatCVE-2017-15721Moderate

irssi: NULL pointer dereference due to incorrectly formatted DCC CTCP messages

Oct 22, 2017

References

openwall.com / lists/oss-security/2017/10/22/4
Mailing ListMitigationPatchThird Party Advisory
irssi.org / security/irssi_sa_2017_10.txt
MitigationPatchVendor Advisory
lists.debian.org / debian-lts-announce/2017/12/msg00022.html
Mailing ListThird Party Advisory
debian.org / security/2017/dsa-4016
Third Party Advisory