high CVSS 7.1

CVE-2024-26763·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: dm-crypt: don't modify the data when using authenticated encryption It was said that authenticated encryption could produce invalid tag when the data that is being encrypted is modified [1]. So, fix this problem by copying the data into the clone bio first and then encrypt them inside the clone bio. This may reduce performance, but it is needed to prevent the user from corrupting the device by writing data with O_DIRECT and modifying them at the same time. [1] https://lore.kernel.org/all/20240207004723.GA35324@sol.localdomain/T/

Severity
high
Software
Kernel
Fixed in
6.7.7
Published
2024-04-03

Affected versions

From: 6.7

Until: 6.7.7

Fixed in: 6.7.7

How to fix this CVE

Update your Linux kernel to version 6.7.7 or later to resolve this dm-crypt data corruption vulnerability. Systems using authenticated encryption modes (such as AES-GCM) with direct I/O writes are at risk of generating invalid authentication tags when data is modified concurrently. Apply the kernel update and reboot your system to activate the fix, which implements proper data isolation between user-space buffers and encrypted clone buffers.

sudo dnf check-update kernel && sudo dnf update kernel

Defensia detects this vulnerability

How to check if you are affected

  1. Run 'uname -r' to check your current kernel version and confirm if it is between 6.7 and 6.7.6 (vulnerable range)
  2. Execute 'dmsetup table' and grep for 'crypt' targets to identify if dm-crypt is actively configured on the system
  3. Check for authenticated encryption cipher modes in dm-crypt targets using 'dmsetup status' and look for entries containing 'aes-gcm' or similar AEAD modes
  4. Verify kernel patch application by checking 'cat /proc/version' post-update to confirm version is 6.7.7 or higher

FAQ

What is CVE-2024-26763?

CVE-2024-26763 is a Linux kernel vulnerability in the dm-crypt subsystem where concurrent modification of user-space data during encryption operations with authenticated encryption modes can result in invalid authentication tags, potentially corrupting encrypted data on disk.

Is CVE-2024-26763 being actively exploited?

No, CVE-2024-26763 is not listed on the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits are available. However, it remains a high-severity issue due to its potential for data corruption.

What versions of Kernel are affected by CVE-2024-26763?

Linux kernel versions 6.7 through 6.7.6 are affected. Version 6.7.7 and later contain the necessary fix.

How do I check if my server is vulnerable to CVE-2024-26763?

Run 'uname -r' and check if the output shows version 6.7.0 through 6.7.6. Additionally, verify dm-crypt is in use by running 'dmsetup table | grep crypt'. If both conditions are true, your system is vulnerable.

Does Defensia detect CVE-2024-26763?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If the Linux kernel is installed on a monitored server and falls within the vulnerable version range, CVE-2024-26763 will appear in your dashboard with remediation steps.

Related Kernel CVEs

CVE-2024-42256CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: cifs: Fix server re-repick on subrequest retry When a subrequest is marked for needing retry, netfs will call cifs_prepare_write() which will make cifs repick the server for the op before renegotiating credits; it then calls cifs_issue_write() which invokes smb2_async_writev() - which re-repicks the server. If a different server is then selected, this causes the increment of server->in_flight to happen against one record and the decrement to happen against another, leading to misaccounting. Fix this by just removing the repick code in smb2_async_writev(). As this is only called from netfslib-driven code, cifs_prepare_write() should always have been called first, and so server should never be NULL and the preparatory step is repeated in the event that we do a retry. The problem manifests as a warning looking something like: WARNING: CPU: 4 PID: 72896 at fs/smb/client/smb2ops.c:97 smb2_add_credits+0x3f0/0x9e0 [cifs] ... RIP: 0010:smb2_add_credits+0x3f0/0x9e0 [cifs] ... smb2_writev_callback+0x334/0x560 [cifs] cifs_demultiplex_thread+0x77a/0x11b0 [cifs] kthread+0x187/0x1d0 ret_from_fork+0x34/0x60 ret_from_fork_asm+0x1a/0x30 Which may be triggered by a number of different xfstests running against an Azure server in multichannel mode. generic/249 seems the most repeatable, but generic/215, generic/249 and generic/308 may also show it.
CVE-2024-38541CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: of: module: add buffer overflow check in of_modalias() In of_modalias(), if the buffer happens to be too small even for the 1st snprintf() call, the len parameter will become negative and str parameter (if not NULL initially) will point beyond the buffer's end. Add the buffer overflow check after the 1st snprintf() call and fix such check after the strlen() call (accounting for the terminating NUL char).
CVE-2021-47548CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: ethernet: hisilicon: hns: hns_dsaf_misc: fix a possible array overflow in hns_dsaf_ge_srst_by_port() The if statement: if (port >= DSAF_GE_NUM) return; limits the value of port less than DSAF_GE_NUM (i.e., 8). However, if the value of port is 6 or 7, an array overflow could occur: port_rst_off = dsaf_dev->mac_cb[port]->port_rst_off; because the length of dsaf_dev->mac_cb is DSAF_MAX_PORT_NUM (i.e., 6). To fix this possible array overflow, we first check port and if it is greater than or equal to DSAF_MAX_PORT_NUM, the function returns.
CVE-2024-38612CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: ipv6: sr: fix invalid unregister error path The error path of seg6_init() is wrong in case CONFIG_IPV6_SEG6_LWTUNNEL is not defined. In that case if seg6_hmac_init() fails, the genl_unregister_family() isn't called. This issue exist since commit 46738b1317e1 ("ipv6: sr: add option to control lwtunnel support"), and commit 5559cea2d5aa ("ipv6: sr: fix possible use-after-free and null-ptr-deref") replaced unregister_pernet_subsys() with genl_unregister_family() in this error path.
CVE-2022-48716CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: ASoC: codecs: wcd938x: fix incorrect used of portid Mixer controls have the channel id in mixer->reg, which is not same as port id. port id should be derived from chan_info array. So fix this. Without this, its possible that we could corrupt struct wcd938x_sdw_priv by accessing port_map array out of range with channel id instead of port id.

References

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