CVE-2018-8897
Vulnérabilité non évaluée
Description
A statement in the System Programming Guide of the Intel 64 and IA-32 Architectures Software Developer's Manual (SDM) was mishandled in the development of some or all operating-system kernels, resulting in unexpected behavior for #DB exceptions that are deferred by MOV SS or POP SS, as demonstrated by (for example) privilege escalation in Windows, macOS, some Xen configurations, or FreeBSD, or a Linux kernel crash. The MOV to SS and POP SS instructions inhibit interrupts (including NMIs), data breakpoints, and single step trap exceptions until the instruction boundary following the next instruction (SDM Vol. 3A; section 6.8.3). (The inhibited data breakpoints are those on memory accessed by the MOV to SS or POP to SS instruction itself.) Note that debug exceptions are not inhibited by the interrupt enable (EFLAGS.IF) system flag (SDM Vol. 3A; section 2.3). If the instruction following the MOV to SS or POP to SS instruction is an instruction like SYSCALL, SYSENTER, INT 3, etc. that transfers control to the operating system at CPL < 3, the debug exception is delivered after the transfer to CPL < 3 is complete. OS kernels may not expect this order of events and may therefore experience unexpected behavior when it occurs.
Gravité et risque d'exploitation
CVE-2018-8897 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 18.48 %, ce qui la place devant 97.2 % des CVE référencées.
Que faire ?
- Vérifiez si le produit concerné est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.
Références
- https://github.com/torvalds/linux/commit/d8ba61ba58c88d5207c1ba2f7d9a2280e7d03be9
- http://openwall.com/lists/oss-security/2018/05/08/4
- http://www.securitytracker.com/id/1040849
- http://www.securityfocus.com/bid/104071
- https://access.redhat.com/errata/RHSA-2018:1350
- https://support.citrix.com/article/CTX234679
- https://access.redhat.com/errata/RHSA-2018:1347
- https://www.exploit-db.com/exploits/44697/
- https://lists.debian.org/debian-lts-announce/2018/05/msg00015.html
- http://www.securitytracker.com/id/1040866
- https://lists.debian.org/debian-lts-announce/2018/11/msg00013.html
- https://lists.debian.org/debian-lts-announce/2018/06/msg00000.html
- https://support.apple.com/HT208742
- https://access.redhat.com/errata/RHSA-2018:1346
- https://access.redhat.com/errata/RHSA-2018:1348
- https://access.redhat.com/errata/RHSA-2018:1354
- https://svnweb.freebsd.org/base?view=revision&revision=333368
- https://www.debian.org/security/2018/dsa-4196
- https://www.freebsd.org/security/advisories/FreeBSD-SA-18:06.debugreg.asc
- http://www.securitytracker.com/id/1040744
- https://www.triplefault.io/2018/05/spurious-db-exceptions-with-pop-ss.html
- https://access.redhat.com/errata/RHSA-2018:1351
- https://bugzilla.redhat.com/show_bug.cgi?id=1567074
- https://xenbits.xen.org/xsa/advisory-260.html
- https://access.redhat.com/errata/RHSA-2018:1319
- https://www.debian.org/security/2018/dsa-4201
- https://help.ecostruxureit.com/display/public/UADCE725/Security+fixes+in+StruxureWare+Data+Center+Expert+v7.6.0
- https://access.redhat.com/errata/RHSA-2018:1355
- https://security.netapp.com/advisory/ntap-20180927-0002/
- https://access.redhat.com/errata/RHSA-2018:1345
- https://www.exploit-db.com/exploits/45024/
- https://access.redhat.com/errata/RHSA-2018:1349
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8897
- https://access.redhat.com/errata/RHSA-2018:1352
- https://access.redhat.com/errata/RHSA-2018:1318
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d8ba61ba58c88d5207c1ba2f7d9a2280e7d03be9
- https://patchwork.kernel.org/patch/10386677/
- https://www.kb.cert.org/vuls/id/631579
- https://github.com/can1357/CVE-2018-8897/
- https://access.redhat.com/errata/RHSA-2018:1524
- http://openwall.com/lists/oss-security/2018/05/08/1
- http://www.securitytracker.com/id/1040861
- https://access.redhat.com/errata/RHSA-2018:1353
- https://usn.ubuntu.com/3641-2/
- https://www.synology.com/support/security/Synology_SA_18_21
- http://www.securitytracker.com/id/1040882
- https://usn.ubuntu.com/3641-1/
- http://www.huawei.com/en/psirt/security-advisories/huawei-sa-20190921-01-debug-en
