What is CVE-2016-9623?

CVE-2016-9623 is a medium-severity vulnerability in Tats W3m, classified under NULL Pointer Dereference. CVSS score: 6.5/10. Published 2016-12-12.

How severe is CVE-2016-9623?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Is CVE-2016-9623 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

NULL pointer dereference in Tats W3m

CVE-2016-9623

An issue was discovered in the Tatsuya Kinoshita w3m fork before 0.5.3-33. w3m allows remote attackers to cause a denial of service (segmentation fault and crash) via a crafted HTML page.

Published 2016-12-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.018 (77.2th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 77th percentile — 77.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.018 · newest: 0.018 · change: 0.000

Affected products

Tats W3m

Weakness classification (CWE)

CWE-476 — NULL Pointer Dereference

Public proof-of-concept exploits

mrash/afl-cve

References

github.com/tats/w3m/issues/33 (Patch, Issue Tracking)
github.com/tats/w3m/blob/master/ChangeLog (Patch, Issue Tracking)
www.openwall.com/lists/oss-security/2016/11/24/1 (mailing-list, Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2016-9623?: CVE-2016-9623 is a medium-severity vulnerability in Tats W3m, classified under NULL Pointer Dereference. CVSS score: 6.5/10. Published 2016-12-12.
How severe is CVE-2016-9623?: Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2016-9623 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.