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TI-2007-01500 Aliases CVE-2007-1558GHSA-jmh6-7c53-fg26

The APOP protocol allows remote attackers to guess the first 3 characters of a password…

Priority LOW 18Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
— Not recorded in CVSS 2.0
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
Partial · None · None
Fix status
Fixed

Attack profile from CVSS 2.0 · NVD. Fix status from CNA and Red Hat.

Summary

The APOP protocol allows remote attackers to guess the first 3 characters of a password via man-in-the-middle (MITM) attacks that use crafted message IDs and MD5 collisions. NOTE: this design-level issue potentially affects all products that use APOP, including (1) Thunderbird 1.x before 1.5.0.12 and 2.x before 2.0.0.4, (2) Evolution, (3) mutt, (4) fetchmail before 6.3.8, (5) SeaMonkey 1.0.x before 1.0.9 and 1.1.x before 1.1.2, (6) Balsa 2.3.16 and earlier, (7) Mailfilter before 0.8.2, and possibly other products.

Why it matters now

EPSS 0.02423 84th percentileScored 2026-11-07
Fix Fixed Red Hat: 7 advisories

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:apop_protocol:apop_protocol:*:*:*:*:*:*:*:*all versionsVulnerableApop Protocol
  • cpe:2.3:a:apop_protocol:apop_protocol:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Apop Protocol

Remediation

Red Hat 7 advisories

  • RHSA-2009:1140 Released 2009-07-02 · Red Hat rating Moderate
    ruby security update
    • Red Hat Enterprise Linux (v. 5 server) ruby-1.8.5-5.el5_3.7, ruby-1.8.5-5.el5_3.7.i386, ruby-1.8.5-5.el5_3.7.ia64 +33
    • Red Hat Enterprise Linux AS version 4 irb-1.8.1-7.el4_8.3, irb-1.8.1-7.el4_8.3.i386, irb-1.8.1-7.el4_8.3.ia64 +25
    • Red Hat Enterprise Linux Desktop (v. 5 client) ruby-1.8.5-5.el5_3.7, ruby-1.8.5-5.el5_3.7.i386, ruby-docs-1.8.5-5.el5_3.7 +11
    • Red Hat Enterprise Linux Desktop Workstation (v. 5 client) ruby-1.8.5-5.el5_3.7, ruby-devel-1.8.5-5.el5_3.7, ruby-devel-1.8.5-5.el5_3.7.i386 +2
    • Red Hat Enterprise Linux Desktop version 4 irb-1.8.1-7.el4_8.3, irb-1.8.1-7.el4_8.3.i386, ruby-1.8.1-7.el4_8.3 +11
    • Red Hat Enterprise Linux ES version 4 irb-1.8.1-7.el4_8.3, irb-1.8.1-7.el4_8.3.i386, irb-1.8.1-7.el4_8.3.ia64 +18
    • Red Hat Enterprise Linux WS version 4 irb-1.8.1-7.el4_8.3, irb-1.8.1-7.el4_8.3.i386, irb-1.8.1-7.el4_8.3.ia64 +18
  • RHSA-2007:0385 Released 2007-06-07 · Red Hat rating Moderate
    fetchmail security update
    • Red Hat Desktop version 3 fetchmail-6.2.0-3.el3.4, fetchmail-6.2.0-3.el3.4.i386
    • Red Hat Enterprise Linux (v. 5 server) fetchmail-6.3.6-1.0.1.el5, fetchmail-6.3.6-1.0.1.el5.i386, fetchmail-6.3.6-1.0.1.el5.ia64 +1
    • Red Hat Enterprise Linux AS (Advanced Server) version 2.1 fetchmail-5.9.0-21.7.3.el2.1.6, fetchmail-5.9.0-21.7.3.el2.1.6.i386, fetchmail-5.9.0-21.7.3.el2.1.6.ia64 +2
    • Red Hat Enterprise Linux AS version 3 fetchmail-6.2.0-3.el3.4, fetchmail-6.2.0-3.el3.4.i386, fetchmail-6.2.0-3.el3.4.ia64 +1
    • Red Hat Enterprise Linux AS version 4 fetchmail-6.2.5-6.0.1.el4, fetchmail-6.2.5-6.0.1.el4.i386, fetchmail-6.2.5-6.0.1.el4.ia64 +1
    • Red Hat Enterprise Linux Desktop Workstation (v. 5 client) fetchmail-6.3.6-1.0.1.el5, fetchmail-6.3.6-1.0.1.el5.i386
    • Red Hat Enterprise Linux Desktop version 4 fetchmail-6.2.5-6.0.1.el4, fetchmail-6.2.5-6.0.1.el4.i386
    • Red Hat Enterprise Linux ES version 2.1 fetchmail-5.9.0-21.7.3.el2.1.6, fetchmail-5.9.0-21.7.3.el2.1.6.i386, fetchmailconf-5.9.0-21.7.3.el2.1.6.i386
    • Red Hat Enterprise Linux ES version 3 fetchmail-6.2.0-3.el3.4, fetchmail-6.2.0-3.el3.4.i386, fetchmail-6.2.0-3.el3.4.ia64
    • Red Hat Enterprise Linux ES version 4 fetchmail-6.2.5-6.0.1.el4, fetchmail-6.2.5-6.0.1.el4.i386, fetchmail-6.2.5-6.0.1.el4.ia64
    • Red Hat Enterprise Linux WS version 2.1 fetchmail-5.9.0-21.7.3.el2.1.6, fetchmail-5.9.0-21.7.3.el2.1.6.i386, fetchmailconf-5.9.0-21.7.3.el2.1.6.i386
    • Red Hat Enterprise Linux WS version 3 fetchmail-6.2.0-3.el3.4, fetchmail-6.2.0-3.el3.4.i386, fetchmail-6.2.0-3.el3.4.ia64
    • Red Hat Enterprise Linux WS version 4 fetchmail-6.2.5-6.0.1.el4, fetchmail-6.2.5-6.0.1.el4.i386, fetchmail-6.2.5-6.0.1.el4.ia64
    • Red Hat Linux Advanced Workstation 2.1 fetchmail-5.9.0-21.7.3.el2.1.6, fetchmail-5.9.0-21.7.3.el2.1.6.ia64, fetchmailconf-5.9.0-21.7.3.el2.1.6.ia64
  • RHSA-2007:0386 Released 2007-06-04 · Red Hat rating Moderate
    mutt security update
    • Red Hat Desktop version 3 mutt-5:1.4.1-5.el3, mutt-5:1.4.1-5.el3.i386
    • Red Hat Enterprise Linux (v. 5 server) mutt-5:1.4.2.2-3.0.2.el5, mutt-5:1.4.2.2-3.0.2.el5.i386, mutt-5:1.4.2.2-3.0.2.el5.ia64 +1
    • Red Hat Enterprise Linux AS version 3 mutt-5:1.4.1-5.el3, mutt-5:1.4.1-5.el3.i386, mutt-5:1.4.1-5.el3.ia64 +1
    • Red Hat Enterprise Linux AS version 4 mutt-5:1.4.1-12.0.3.el4, mutt-5:1.4.1-12.0.3.el4.i386, mutt-5:1.4.1-12.0.3.el4.ia64 +1
    • Red Hat Enterprise Linux Desktop (v. 5 client) mutt-5:1.4.2.2-3.0.2.el5, mutt-5:1.4.2.2-3.0.2.el5.i386
    • Red Hat Enterprise Linux Desktop version 4 mutt-5:1.4.1-12.0.3.el4, mutt-5:1.4.1-12.0.3.el4.i386
    • Red Hat Enterprise Linux ES version 3 mutt-5:1.4.1-5.el3, mutt-5:1.4.1-5.el3.i386, mutt-5:1.4.1-5.el3.ia64
    • Red Hat Enterprise Linux ES version 4 mutt-5:1.4.1-12.0.3.el4, mutt-5:1.4.1-12.0.3.el4.i386, mutt-5:1.4.1-12.0.3.el4.ia64
    • Red Hat Enterprise Linux WS version 3 mutt-5:1.4.1-5.el3, mutt-5:1.4.1-5.el3.i386, mutt-5:1.4.1-5.el3.ia64
    • Red Hat Enterprise Linux WS version 4 mutt-5:1.4.1-12.0.3.el4, mutt-5:1.4.1-12.0.3.el4.i386, mutt-5:1.4.1-12.0.3.el4.ia64
Show 4 more Red Hat advisories
  • RHSA-2007:0402 Released 2007-05-31 · Red Hat rating Critical
    seamonkey security update
    • Red Hat Desktop version 3 seamonkey-1.0.9-0.1.el3, seamonkey-1.0.9-0.1.el3.i386, seamonkey-chat-1.0.9-0.1.el3 +17
    • Red Hat Enterprise Linux AS (Advanced Server) version 2.1 seamonkey-1.0.9-0.1.el2, seamonkey-1.0.9-0.1.el2.i386, seamonkey-1.0.9-0.1.el2.ia64 +18
    • Red Hat Enterprise Linux AS version 3 seamonkey-1.0.9-0.1.el3, seamonkey-1.0.9-0.1.el3.i386, seamonkey-1.0.9-0.1.el3.ia64 +37
    • Red Hat Enterprise Linux AS version 4 devhelp-0.10-0.8.el4, devhelp-0.10-0.8.el4.i386, devhelp-0.10-0.8.el4.ppc +27
    • Red Hat Enterprise Linux Desktop version 4 devhelp-0.10-0.8.el4, devhelp-0.10-0.8.el4.i386, devhelp-devel-0.10-0.8.el4 +13
    • Red Hat Enterprise Linux ES version 2.1 seamonkey-1.0.9-0.1.el2, seamonkey-1.0.9-0.1.el2.i386, seamonkey-chat-1.0.9-0.1.el2.i386 +8
    • Red Hat Enterprise Linux ES version 3 seamonkey-1.0.9-0.1.el3, seamonkey-1.0.9-0.1.el3.i386, seamonkey-1.0.9-0.1.el3.ia64 +27
    • Red Hat Enterprise Linux ES version 4 devhelp-0.10-0.8.el4, devhelp-0.10-0.8.el4.i386, devhelp-devel-0.10-0.8.el4 +19
    • Red Hat Enterprise Linux WS version 2.1 seamonkey-1.0.9-0.1.el2, seamonkey-1.0.9-0.1.el2.i386, seamonkey-chat-1.0.9-0.1.el2.i386 +8
    • Red Hat Enterprise Linux WS version 3 seamonkey-1.0.9-0.1.el3, seamonkey-1.0.9-0.1.el3.i386, seamonkey-1.0.9-0.1.el3.ia64 +27
    • Red Hat Enterprise Linux WS version 4 devhelp-0.10-0.8.el4, devhelp-0.10-0.8.el4.i386, devhelp-devel-0.10-0.8.el4 +19
    • Red Hat Linux Advanced Workstation 2.1 seamonkey-1.0.9-0.1.el2, seamonkey-1.0.9-0.1.el2.ia64, seamonkey-chat-1.0.9-0.1.el2.ia64 +8
  • RHSA-2007:0401 Released 2007-05-31 · Red Hat rating Critical
    thunderbird security update
    • Red Hat Enterprise Linux AS version 4 thunderbird-1.5.0.12-0.1.el4, thunderbird-1.5.0.12-0.1.el4.i386, thunderbird-1.5.0.12-0.1.el4.ia64 +1
    • Red Hat Enterprise Linux Desktop (v. 5 client) thunderbird-1.5.0.12-1.el5, thunderbird-1.5.0.12-1.el5.i386
    • Red Hat Enterprise Linux Desktop version 4 thunderbird-1.5.0.12-0.1.el4, thunderbird-1.5.0.12-0.1.el4.i386
    • Red Hat Enterprise Linux ES version 4 thunderbird-1.5.0.12-0.1.el4, thunderbird-1.5.0.12-0.1.el4.i386, thunderbird-1.5.0.12-0.1.el4.ia64
    • Red Hat Enterprise Linux Optional Productivity Applications (v. 5 server) thunderbird-1.5.0.12-1.el5, thunderbird-1.5.0.12-1.el5.i386
    • Red Hat Enterprise Linux WS version 4 thunderbird-1.5.0.12-0.1.el4, thunderbird-1.5.0.12-0.1.el4.i386, thunderbird-1.5.0.12-0.1.el4.ia64
  • RHSA-2007:0344 Released 2007-05-30 · Red Hat rating Moderate
    evolution-data-server security update
    • Red Hat Enterprise Linux (v. 5 server) evolution-data-server-1.8.0-15.0.3.el5, evolution-data-server-1.8.0-15.0.3.el5.i386, evolution-data-server-1.8.0-15.0.3.el5.ia64 +5
    • Red Hat Enterprise Linux Desktop (v. 5 client) evolution-data-server-1.8.0-15.0.3.el5, evolution-data-server-1.8.0-15.0.3.el5.i386
    • Red Hat Enterprise Linux Desktop Workstation (v. 5 client) evolution-data-server-1.8.0-15.0.3.el5, evolution-data-server-devel-1.8.0-15.0.3.el5, evolution-data-server-devel-1.8.0-15.0.3.el5.i386
  • RHSA-2007:0353 Released 2007-05-17 · Red Hat rating Moderate
    evolution security update
    • Red Hat Desktop version 3 evolution-1.4.5-20.el3, evolution-1.4.5-20.el3.i386, evolution-devel-1.4.5-20.el3 +1
    • Red Hat Enterprise Linux AS version 3 evolution-1.4.5-20.el3, evolution-1.4.5-20.el3.i386, evolution-1.4.5-20.el3.ia64 +5
    • Red Hat Enterprise Linux AS version 4 evolution-2.0.2-35.0.2.el4, evolution-2.0.2-35.0.2.el4.i386, evolution-2.0.2-35.0.2.el4.ia64 +5
    • Red Hat Enterprise Linux Desktop version 4 evolution-2.0.2-35.0.2.el4, evolution-2.0.2-35.0.2.el4.i386, evolution-devel-2.0.2-35.0.2.el4 +1
    • Red Hat Enterprise Linux ES version 3 evolution-1.4.5-20.el3, evolution-1.4.5-20.el3.i386, evolution-1.4.5-20.el3.ia64 +3
    • Red Hat Enterprise Linux ES version 4 evolution-2.0.2-35.0.2.el4, evolution-2.0.2-35.0.2.el4.i386, evolution-2.0.2-35.0.2.el4.ia64 +3
    • Red Hat Enterprise Linux WS version 3 evolution-1.4.5-20.el3, evolution-1.4.5-20.el3.i386, evolution-1.4.5-20.el3.ia64 +3
    • Red Hat Enterprise Linux WS version 4 evolution-2.0.2-35.0.2.el4, evolution-2.0.2-35.0.2.el4.i386, evolution-2.0.2-35.0.2.el4.ia64 +3

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Desktop version 3Fixed RHSA-2007:0353, RHSA-2007:0385, RHSA-2007:0386, RHSA-2007:0402
Red Hat Enterprise Linux (v. 5 server)Fixed RHSA-2007:0344, RHSA-2007:0385, RHSA-2007:0386, RHSA-2009:1140
Red Hat Enterprise Linux AS (Advanced Server) version 2.1 Fixed RHSA-2007:0385, RHSA-2007:0402
Red Hat Enterprise Linux AS version 3Fixed RHSA-2007:0353, RHSA-2007:0385, RHSA-2007:0386, RHSA-2007:0402
Red Hat Enterprise Linux AS version 4Fixed RHSA-2007:0353, RHSA-2007:0385, RHSA-2007:0386, RHSA-2007:0401, RHSA-2007:0402, RHSA-2009:1140
Red Hat Enterprise Linux Desktop (v. 5 client)Fixed RHSA-2007:0344, RHSA-2007:0386, RHSA-2007:0401, RHSA-2009:1140
Red Hat Enterprise Linux Desktop Workstation (v. 5 client)Fixed RHSA-2007:0344, RHSA-2007:0385, RHSA-2009:1140
Red Hat Enterprise Linux Desktop version 4Fixed RHSA-2007:0353, RHSA-2007:0385, RHSA-2007:0386, RHSA-2007:0401, RHSA-2007:0402, RHSA-2009:1140
Red Hat Enterprise Linux ES version 2.1Fixed RHSA-2007:0385, RHSA-2007:0402
Red Hat Enterprise Linux ES version 3Fixed RHSA-2007:0353, RHSA-2007:0385, RHSA-2007:0386, RHSA-2007:0402
Red Hat Enterprise Linux ES version 4Fixed RHSA-2007:0353, RHSA-2007:0385, RHSA-2007:0386, RHSA-2007:0401, RHSA-2007:0402, RHSA-2009:1140
Red Hat Enterprise Linux Optional Productivity Applications (v. 5 server)Fixed RHSA-2007:0401
Red Hat Enterprise Linux WS version 2.1Fixed RHSA-2007:0385, RHSA-2007:0402
Red Hat Enterprise Linux WS version 3Fixed RHSA-2007:0353, RHSA-2007:0385, RHSA-2007:0386, RHSA-2007:0402
Red Hat Enterprise Linux WS version 4Fixed RHSA-2007:0353, RHSA-2007:0385, RHSA-2007:0386, RHSA-2007:0401, RHSA-2007:0402, RHSA-2009:1140
Red Hat Linux Advanced Workstation 2.1Fixed RHSA-2007:0385, RHSA-2007:0402

Timeline

  1. 2026-10-02 Threatist record created from CVE-2007-1558
  2. 2026-10-03 Alias added: GHSA-jmh6-7c53-fg26

References

Patch 2

Advisory 25

Other 21

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences