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    CVE-2021-41991

    The in-memory certificate cache in strongSwan before 5.9.4 has a remote integer overflow upon receiving many requests with different certificates to fill the cache and later trigger the replacement of cache entries. The code attempts to select a less-often-used cache entry by means of a random number generator, but this is not done correctly. Remote code execution might be a slight possibility.

    Published:Oct 18, 2021
    Last Modified:Nov 21, 2024
    EPS:Oct 18, 2021
    EPSS Score:0.01696
    CVSS Score:7.5

    Affected Products

    Vendor
    Debian
    Product
    Debian Linux
    Vendor
    Fedoraproject
    Product
    Fedora
    Vendor
    Siemens
    Product
    Cp 1543-1
    Vendor
    Siemens
    Product
    Cp 1543-1 Firmware
    Vendor
    Siemens
    Product
    Scalance Sc622-2c
    Vendor
    Siemens
    Product
    Scalance Sc622-2c Firmware
    Vendor
    Siemens
    Product
    Scalance Sc632-2c
    Vendor
    Siemens
    Product
    Scalance Sc632-2c Firmware
    Vendor
    Siemens
    Product
    Scalance Sc636-2c
    Vendor
    Siemens
    Product
    Scalance Sc636-2c Firmware
    Vendor
    Siemens
    Product
    Scalance Sc642-2c
    Vendor
    Siemens
    Product
    Scalance Sc642-2c Firmware
    Vendor
    Siemens
    Product
    Scalance Sc646-2c
    Vendor
    Siemens
    Product
    Scalance Sc646-2c Firmware
    Vendor
    Siemens
    Product
    Simatic Cp 1242-7 Gprs V2
    Vendor
    Siemens
    Product
    Simatic Cp 1242-7 Gprs V2 Firmware
    Vendor
    Siemens
    Product
    Simatic Cp 1243-1
    Vendor
    Siemens
    Product
    Simatic Cp 1243-1 Firmware
    Vendor
    Siemens
    Product
    Simatic Cp 1243-7 Lte\/us
    Vendor
    Siemens
    Product
    Simatic Cp 1243-7 Lte\/us Firmware
    Vendor
    Siemens
    Product
    Simatic Cp 1542sp-1
    Vendor
    Siemens
    Product
    Simatic Cp 1542sp-1 Firmware
    Vendor
    Siemens
    Product
    Simatic Cp 1542sp-1 Irc
    Vendor
    Siemens
    Product
    Simatic Cp 1542sp-1 Irc Firmware
    Vendor
    Siemens
    Product
    Simatic Cp 1543sp-1
    Vendor
    Siemens
    Product
    Simatic Cp 1543sp-1 Firmware
    Vendor
    Siemens
    Product
    Simatic Net Cp1243-7 Lte Eu
    Vendor
    Siemens
    Product
    Simatic Net Cp1243-7 Lte Eu Firmware
    Vendor
    Siemens
    Product
    Simatic Net Cp 1243-8 Irc
    Vendor
    Siemens
    Product
    Simatic Net Cp 1243-8 Irc Firmware
    Vendor
    Siemens
    Product
    Simatic Net Cp 1545-1
    Vendor
    Siemens
    Product
    Simatic Net Cp 1545-1 Firmware
    Vendor
    Siemens
    Product
    Sinema Remote Connect Server
    Vendor
    Siemens
    Product
    Siplus Et 200sp Cp 1542sp-1 Irc Tx Rail
    Vendor
    Siemens
    Product
    Siplus Et 200sp Cp 1542sp-1 Irc Tx Rail Firmware
    Vendor
    Siemens
    Product
    Siplus Et 200sp Cp 1543sp-1 Isec
    Vendor
    Siemens
    Product
    Siplus Et 200sp Cp 1543sp-1 Isec Firmware
    Vendor
    Siemens
    Product
    Siplus Et 200sp Cp 1543sp-1 Isec Tx Rail
    Vendor
    Siemens
    Product
    Siplus Et 200sp Cp 1543sp-1 Isec Tx Rail Firmware
    Vendor
    Siemens
    Product
    Siplus Net Cp 1543-1
    Vendor
    Siemens
    Product
    Siplus Net Cp 1543-1 Firmware
    Vendor
    Siemens
    Product
    Siplus S7-1200 Cp 1243-1
    Vendor
    Siemens
    Product
    Siplus S7-1200 Cp 1243-1 Firmware
    Vendor
    Siemens
    Product
    Siplus S7-1200 Cp 1243-1 Rail
    Vendor
    Siemens
    Product
    Siplus S7-1200 Cp 1243-1 Rail Firmware
    Vendor
    Strongswan
    Product
    Strongswan

    Exploits

    No exploit reference

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    References

    https://cert-portal.siemens.com/productcert/pdf/ssa-539476.pdf
    https://github.com/strongswan/strongswan/releases/tag/5.9.4
    https://lists.debian.org/debian-lts-announce/2021/10/msg00014.html
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5FJSATD2R2XHTG4P63GCMQ2N7EWKMME5/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WQSQ3BEC22NF4NCDZVCT4P3Q2ZIAJXGJ/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y3TQ32JLJOBJDB2EJKSX2PBPB5NFG2D4/
    https://www.debian.org/security/2021/dsa-4989
    https://www.strongswan.org/blog/2021/10/18/strongswan-vulnerability-%28cve-2021-41991%29.html
    https://cert-portal.siemens.com/productcert/pdf/ssa-539476.pdf
    https://github.com/strongswan/strongswan/releases/tag/5.9.4
    https://lists.debian.org/debian-lts-announce/2021/10/msg00014.html
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5FJSATD2R2XHTG4P63GCMQ2N7EWKMME5/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WQSQ3BEC22NF4NCDZVCT4P3Q2ZIAJXGJ/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y3TQ32JLJOBJDB2EJKSX2PBPB5NFG2D4/
    https://www.debian.org/security/2021/dsa-4989
    https://www.strongswan.org/blog/2021/10/18/strongswan-vulnerability-%28cve-2021-41991%29.html

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High