CVSS: 4.7EPSS: 0%CPEs: 2EXPL: 0CVE-2021-4001
https://notcve.org/view.php?id=CVE-2021-4001
A race condition was found in the Linux kernel's ebpf verifier between bpf_map_update_elem and bpf_map_freeze due to a missing lock in kernel/bpf/syscall.c. In this flaw, a local user with a special privilege (cap_sys_admin or cap_bpf) can modify the frozen mapped address space. This flaw affects kernel versions prior to 5.16 rc2. Se ha encontrado una condición de carrera en el verificador ebpf del kernel de Linux entre las funciones bpf_map_update_elem y bpf_map_freeze debido a la falta de un bloqueo en el archivo kernel/bpf/syscall.c. En este fallo, un usuario local con un privilegio especial (cap_sys_admin o cap_bpf) puede modificar el espacio de direcciones mapeado congelado. • https://bugzilla.redhat.com/show_bug.cgi?id=2025645 https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4c19e102178ccc05988101887c25ae53 • CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition •
CVSS: 5.1EPSS: 0%CPEs: 10EXPL: 1CVE-2021-4002 – kernel: possible leak or coruption of data residing on hugetlbfs
https://notcve.org/view.php?id=CVE-2021-4002
A memory leak flaw in the Linux kernel's hugetlbfs memory usage was found in the way the user maps some regions of memory twice using shmget() which are aligned to PUD alignment with the fault of some of the memory pages. A local user could use this flaw to get unauthorized access to some data. Se encontró un fallo de pérdida de memoria en el uso de memoria hugetlbfs del kernel de Linux en la forma en que el usuario mapea algunas regiones de memoria dos veces usando shmget() que están alineadas a la alineación PUD con el fallo de algunas de las páginas de memoria. Un usuario local podría usar este fallo para conseguir acceso no autorizado a algunos datos • https://bugzilla.redhat.com/show_bug.cgi?id=2025726 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=13e4ad2ce8df6e058ef482a31fdd81c725b0f7ea https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a4a118f2eead1d6c49e00765de89878288d4b890 https://lists.debian.org/debian-lts-announce/2022/03/msg00011.html https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html https://www.debian.org/security/2022/dsa-5096 https://www.openwall.com/list • CWE-401: Missing Release of Memory after Effective Lifetime CWE-459: Incomplete Cleanup •
CVSS: 6.5EPSS: 0%CPEs: 4EXPL: 0CVE-2021-28715
https://notcve.org/view.php?id=CVE-2021-28715
Guest can force Linux netback driver to hog large amounts of kernel memory T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Incoming data packets for a guest in the Linux kernel's netback driver are buffered until the guest is ready to process them. There are some measures taken for avoiding to pile up too much data, but those can be bypassed by the guest: There is a timeout how long the client side of an interface can stop consuming new packets before it is assumed to have stalled, but this timeout is rather long (60 seconds by default). Using a UDP connection on a fast interface can easily accumulate gigabytes of data in that time. (CVE-2021-28715) The timeout could even never trigger if the guest manages to have only one free slot in its RX queue ring page and the next package would require more than one free slot, which may be the case when using GSO, XDP, or software hashing. • https://lists.debian.org/debian-lts-announce/2022/03/msg00011.html https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html https://www.debian.org/security/2022/dsa-5050 https://www.debian.org/security/2022/dsa-5096 https://xenbits.xenproject.org/xsa/advisory-392.txt • CWE-770: Allocation of Resources Without Limits or Throttling •
CVSS: 6.5EPSS: 0%CPEs: 3EXPL: 0CVE-2021-28714
https://notcve.org/view.php?id=CVE-2021-28714
Guest can force Linux netback driver to hog large amounts of kernel memory T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Incoming data packets for a guest in the Linux kernel's netback driver are buffered until the guest is ready to process them. There are some measures taken for avoiding to pile up too much data, but those can be bypassed by the guest: There is a timeout how long the client side of an interface can stop consuming new packets before it is assumed to have stalled, but this timeout is rather long (60 seconds by default). Using a UDP connection on a fast interface can easily accumulate gigabytes of data in that time. (CVE-2021-28715) The timeout could even never trigger if the guest manages to have only one free slot in its RX queue ring page and the next package would require more than one free slot, which may be the case when using GSO, XDP, or software hashing. • https://lists.debian.org/debian-lts-announce/2022/03/msg00011.html https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html https://www.debian.org/security/2022/dsa-5050 https://www.debian.org/security/2022/dsa-5096 https://xenbits.xenproject.org/xsa/advisory-392.txt • CWE-770: Allocation of Resources Without Limits or Throttling •
CVSS: 7.5EPSS: 0%CPEs: 44EXPL: 1CVE-2021-45485 – kernel: information leak in the IPv6 implementation
https://notcve.org/view.php?id=CVE-2021-45485
In the IPv6 implementation in the Linux kernel before 5.13.3, net/ipv6/output_core.c has an information leak because of certain use of a hash table which, although big, doesn't properly consider that IPv6-based attackers can typically choose among many IPv6 source addresses. En la implementación de IPv6 en el kernel de Linux versiones anteriores a 5.13.3, el archivo net/ipv6/output_core.c presenta un filtrado de información debido a determinado uso de una tabla hash que, aunque es grande, no considera apropiadamente que atacantes basados en IPv6 pueden elegir típicamente entre muchas direcciones de origen IPv6 An information leak flaw was found in the Linux kernel’s IPv6 implementation in the __ipv6_select_ident in net/ipv6/output_core.c function. The use of a small hash table in IP ID generation allows a remote attacker to reveal sensitive information. • https://github.com/Satheesh575555/linux-4.19.72_CVE-2021-45485 https://arxiv.org/pdf/2112.09604.pdf https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.3 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=62f20e068ccc50d6ab66fdb72ba90da2b9418c99 https://security.netapp.com/advisory/ntap-20220121-0001 https://www.oracle.com/security-alerts/cpujul2022.html https://access.redhat.com/security/cve/CVE-2021-45485 https://bugzilla.redhat.com/show_bug. • CWE-327: Use of a Broken or Risky Cryptographic Algorithm •