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chore(deps): update rust crate bytes to v1.11.1 [security] - autoclosed#362

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chore(deps): update rust crate bytes to v1.11.1 [security] - autoclosed#362
renovate[bot] wants to merge 1 commit intomasterfrom
renovate/crate-bytes-vulnerability

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@renovate renovate bot commented Feb 3, 2026

This PR contains the following updates:

Package Type Update Change
bytes dependencies patch 1.11.01.11.1

GitHub Vulnerability Alerts

CVE-2026-25541

Details

In the unique reclaim path of BytesMut::reserve, the condition

if v_capacity >= new_cap + offset

uses an unchecked addition. When new_cap + offset overflows usize in release builds, this condition may incorrectly pass, causing self.cap to be set to a value that exceeds the actual allocated capacity. Subsequent APIs such as spare_capacity_mut() then trust this corrupted cap value and may create out-of-bounds slices, leading to UB.

This behavior is observable in release builds (integer overflow wraps), whereas debug builds panic due to overflow checks.

PoC

use bytes::*;

fn main() {
    let mut a = BytesMut::from(&b"hello world"[..]);
    let mut b = a.split_off(5);

    // Ensure b becomes the unique owner of the backing storage
    drop(a);

    // Trigger overflow in new_cap + offset inside reserve
    b.reserve(usize::MAX - 6);

    // This call relies on the corrupted cap and may cause UB & HBO
    b.put_u8(b'h');
}

Workarounds

Users of BytesMut::reserve are only affected if integer overflow checks are configured to wrap. When integer overflow is configured to panic, this issue does not apply.

This vulnerability is also known as RUSTSEC-2026-0007.


Release Notes

tokio-rs/bytes (bytes)

v1.11.1

Compare Source

  • Fix integer overflow in BytesMut::reserve

Configuration

📅 Schedule: Branch creation - "" (UTC), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.


  • If you want to rebase/retry this PR, check this box

This PR was generated by Mend Renovate. View the repository job log.

@renovate renovate bot force-pushed the renovate/crate-bytes-vulnerability branch from 37ed573 to fc7be0b Compare March 9, 2026 13:57
@renovate renovate bot changed the title chore(deps): update rust crate bytes to v1.11.1 [security] chore(deps): update rust crate bytes to v1.11.1 [security] - autoclosed Mar 9, 2026
@renovate renovate bot closed this Mar 9, 2026
@renovate renovate bot deleted the renovate/crate-bytes-vulnerability branch March 9, 2026 14:07
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