The APOP protocol allows remote attackers to guess the first 3 characters of a password via man-in-the-middle (MITM) attacks that use…

Description

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.

Scores

EPSS (exploitation in 30 days)

2.4% · top 16% of all CVEs (4 Nov 2026)

The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 2.6.

Weakness

• n/a

Affected products

• n/a

  • affected n/a

References (72)

• 25496 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• 25529 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• http://sourceforge.net/forum/forum.php?forum_id=683706 (opens in a new tab)x_refsource_CONFIRMx_transferred
• http://docs.info.apple.com/article.html?artnum=305530 (opens in a new tab)x_refsource_CONFIRMx_transferred
• http://www.claws-mail.org/news.php (opens in a new tab)x_refsource_CONFIRMx_transferred
• MDKSA-2007:107 (opens in a new tab)vendor-advisoryx_refsource_MANDRIVAx_transferred
• 2007-0024 (opens in a new tab)vendor-advisoryx_refsource_TRUSTIXx_transferred
• 20070403 Re: APOP vulnerability (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
• 25894 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• 20070615 rPSA-2007-0122-1 evolution-data-server (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
• ADV-2007-1939 (opens in a new tab)vdb-entryx_refsource_VUPENx_transferred
• 26083 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• ADV-2007-1468 (opens in a new tab)vdb-entryx_refsource_VUPENx_transferred
• RHSA-2009:1140 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• HPSBUX02156 (opens in a new tab)vendor-advisoryx_refsource_HPx_transferred
• 20070531 FLEA-2007-0023-1: firefox (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
• 26415 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• http://fetchmail.berlios.de/fetchmail-SA-2007-01.txt (opens in a new tab)x_refsource_CONFIRMx_transferred
• [oss-security] 20090818 Re: CVE-2007-1558 update (was: mailfilter 0.8.2 fixes CVE-2007-1558 (APOP)) (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• APPLE-SA-2007-05-24 (opens in a new tab)vendor-advisoryx_refsource_APPLEx_transferred
• SUSE-SR:2007:014 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
• 25402 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• HPSBUX02153 (opens in a new tab)vendor-advisoryx_refsource_HPx_transferred
• 20070402 APOP vulnerability (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
• SUSE-SA:2007:036 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
• GLSA-200706-06 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
• http://sylpheed.sraoss.jp/en/news.html (opens in a new tab)x_refsource_CONFIRMx_transferred
• 25534 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• ADV-2007-1994 (opens in a new tab)vdb-entryx_refsource_VUPENx_transferred
• SSA:2007-152-02 (opens in a new tab)vendor-advisoryx_refsource_SLACKWAREx_transferred
• 23257 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
• USN-469-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
• MDKSA-2007:131 (opens in a new tab)vendor-advisoryx_refsource_MANDRIVAx_transferred
• DSA-1305 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
• https://issues.rpath.com/browse/RPL-1231 (opens in a new tab)x_refsource_CONFIRMx_transferred
• ADV-2007-1467 (opens in a new tab)vdb-entryx_refsource_VUPENx_transferred
• http://www.mozilla.org/security/announce/2007/mfsa2007-15.html (opens in a new tab)x_refsource_CONFIRMx_transferred
• ADV-2007-2788 (opens in a new tab)vdb-entryx_refsource_VUPENx_transferred
• https://issues.rpath.com/browse/RPL-1424 (opens in a new tab)x_refsource_CONFIRMx_transferred
• 25664 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• MDKSA-2007:119 (opens in a new tab)vendor-advisoryx_refsource_MANDRIVAx_transferred
• 25546 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• RHSA-2007:0353 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• RHSA-2007:0385 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• 25858 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• 25798 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• 25353 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• ADV-2008-0082 (opens in a new tab)vdb-entryx_refsource_VUPENx_transferred
• [oss-security] 20090815 mailfilter 0.8.2 fixes CVE-2007-1558 (APOP) (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• RHSA-2007:0401 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• 2007-0019 (opens in a new tab)vendor-advisoryx_refsource_TRUSTIXx_transferred
• 25476 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• 35699 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• MDKSA-2007:113 (opens in a new tab)vendor-advisoryx_refsource_MANDRIVAx_transferred
• [balsa-list] 20070704 balsa-2.3.17 released (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• MDKSA-2007:105 (opens in a new tab)vendor-advisoryx_refsource_MANDRIVAx_transferred
• RHSA-2007:0386 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• https://issues.rpath.com/browse/RPL-1232 (opens in a new tab)x_refsource_CONFIRMx_transferred
• 25750 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• 20070619 FLEA-2007-0026-1: evolution-data-server (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
• DSA-1300 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
• 25559 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
• ADV-2007-1466 (opens in a new tab)vdb-entryx_refsource_VUPENx_transferred
• 1018008 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
• oval:org.mitre.oval:def:9782 (opens in a new tab)vdb-entrysignaturex_refsource_OVALx_transferred
• RHSA-2007:0402 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• ADV-2007-1480 (opens in a new tab)vdb-entryx_refsource_VUPENx_transferred
• USN-520-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
• TA07-151A (opens in a new tab)third-party-advisoryx_refsource_CERTx_transferred
• RHSA-2007:0344 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• 20070620 FLEA-2007-0027-1: thunderbird (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
• http://balsa.gnome.org/download.html (opens in a new tab)x_refsource_CONFIRMx_transferred

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2007-1558](https://trackcve.app/badge/CVE-2007-1558.svg)](https://trackcve.app/cve/CVE-2007-1558)

Record last updated 7 Aug 2024, 12:59 UTC.