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Fencer Intel
medium 4.3

CVE-2011-0633 json

The Net::HTTPS module in libwww-perl (LWP) before 6.00, as used in WWW::Mechanize, LWP::UserAgent, and other products, when running in envi…

published 2011-05-13 15 y ago modified 2026-06-16 4 mo ago also EUVD-2011-0651

cvss
4.3
version 2.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
4.2%
EPSS 4.2% chance of exploitation in 30 days, percentile 91%
public exploits
0
none known

Summary

The Net::HTTPS module in libwww-perl (LWP) before 6.00, as used in WWW::Mechanize, LWP::UserAgent, and other products, when running in environments that do not set the If-SSL-Cert-Subject header, does not enable full validation of SSL certificates by default, which allows remote attackers to spoof servers via man-in-the-middle (MITM) attacks involving hostnames that are not properly validated. NOTE: it could be argued that this is a design limitation of the Net::HTTPS API, and separate implementations should be independently assigned CVE identifiers for not working around this limitation. However, because this API was modified within LWP, a single CVE identifier has been assigned.

Patch / fix

  • libwww-perl Debian 14, Debian 13, Debian 12 6.01-1

debian advisories DEBIAN-CVE-2011-0633

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2011-0633 updated cvss 5.8

perl-libwww-perl: no hostname check against SSL certificate name by default

  • Red Hat Enterprise Linux 4 perl-libwww-perl Red Hat Enterprise Linux 5 perl-libwww-perl Red Hat Enterprise Linux 6 perl-libwww-perl
    affected: no fix planned “Will not fix”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

4.25% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 2.0 4.3 AV:N/AC:M/Au:N/C:N/I:P/A:N

Classification

Weakness
  • CWE-20 Improper Input Validation

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.