Not sure if this is high enough severity for Release-Block-Beta but this code is in M69.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ac46ca48dcac85e0822478a0dedb11d5616daa3a

commit ac46ca48dcac85e0822478a0dedb11d5616daa3a
Author: Wan-Teh Chang <wtc@google.com>
Date: Tue Aug 07 23:57:48 2018

Roll src/third_party/libaom/source/libaom/ bc484c485..7a76b645a (72 commits)

https://aomedia.googlesource.com/aom.git/+log/bc484c485277..7a76b645a08c

$ git log bc484c485..7a76b645a --date=short --no-merges --format='%ad %ae %s'
2018-08-06 tomfinegan Move aom_read_obu_header from exports_test to exports_dec
2018-08-06 wtc Add a regression test for  bug oss-fuzz:9720 .
2018-08-06 tomfinegan av1_txfm_test: exclude from shared lib tests.
2018-08-03 mbonadei aomenc: replace uint16 with uint16_t
2018-08-06 ranjit.tulabandu Fix crash issue with monochrome content
2018-08-01 ranjit.tulabandu Fix issues in interpolation filter selection
2018-08-03 urvang Refactor code in setup_ref_mv_list.
2018-08-03 urvang Introduce read_delta_q_params() function.
2018-08-03 chiyotsai Remove repeated code in encode_rd_sb_row
2018-08-03 chiyotsai Replace is_single_inter_mode with is_inter_singleref_mode
2018-08-04 wtc read_tile_info: Validate context_update_tile_id.
2018-08-04 wtc Fix spelling mistake: partiton => partition.
2018-08-03 wtc Document get_partition_subsize and ss_size_lookup.
2018-08-03 debargha Make ss_size lookup same as the spec
2018-08-03 urvang Rename some intra mode functions for clarity.
2018-08-03 urvang Introduce write_intra_prediction_modes() func.
2018-08-03 sarahparker Clean up show_existing_frame decision
2018-08-03 urvang wiener_test: Dedup compute_stats_win* funcs.
2018-08-03 urvang Introduce write_delta_q_params() function.
2018-08-02 wtc Add comments for width/height lookup tables.
(...)

Created with:
  roll-dep src/third_party/libaom/source/libaom
R=johannkoenig@google.com,urvang@chromium.org

BUG= 871928 
BUG= oss-fuzz:9720 

Change-Id: Ie58f1c92c5cac29d9a6b98de1871620f4467a567
Reviewed-on: https://chromium-review.googlesource.com/1166147
Reviewed-by: Johann Koenig <johannkoenig@google.com>
Commit-Queue: Wan-Teh Chang <wtc@google.com>
Cr-Commit-Position: refs/heads/master@{#581396}
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/DEPS
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/README.chromium
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/libaom_srcs.gni
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/config/aom_version.h
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm-neon-cpu-detect/config/aom_config.asm
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm-neon-cpu-detect/config/aom_config.c
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm-neon-cpu-detect/config/aom_config.h
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm-neon/config/aom_config.asm
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm-neon/config/aom_config.c
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm-neon/config/aom_config.h
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm/config/aom_config.asm
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm/config/aom_config.c
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm/config/aom_config.h
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm64/config/aom_config.asm
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm64/config/aom_config.c
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/arm64/config/aom_config.h
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/generic/config/aom_config.asm
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/generic/config/aom_config.c
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/generic/config/aom_config.h
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/ia32/config/aom_config.asm
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/ia32/config/aom_config.c
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/ia32/config/aom_config.h
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/x64/config/aom_config.asm
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/linux/x64/config/aom_config.h
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/win/ia32/config/aom_config.asm
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/win/ia32/config/aom_config.c
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/win/ia32/config/aom_config.h
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/win/x64/config/aom_config.asm
[modify] https://crrev.com/ac46ca48dcac85e0822478a0dedb11d5616daa3a/third_party/libaom/source/config/win/x64/config/aom_config.h

This is a serious security regression. If you are not able to fix this quickly, please revert the change that introduced it.

If this doesn't affect a release branch, or has not been properly classified for severity, please update the Security_Impact or Security_Severity labels, and remove the ReleaseBlock label. To disable this altogether, apply ReleaseBlock-NA.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

I'd like to request merge approval for M69:
https://chromium-review.googlesource.com/c/chromium/src/+/1168148

The only libaom change in this DEPS roll is:
https://aomedia-review.googlesource.com/c/aom/+/67281

+awhalley@ (Security TPM) for M69 merge review.

This bug requires manual review: DEPS changes referenced in bugdroid comments.
Please contact the milestone owner if you have questions.
Owners: amineer@(Android), kariahda@(iOS), cindyb@(ChromeOS), govind@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Please mark security bugs as fixed as soon as the fix lands, and before requesting merges. This update is based on the merge- labels applied to this issue. Please reopen if this update was incorrect.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

govind - good for 69

Approving merge to M69 branch 3497 based on comment #12, pls merge ASAP.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/5207ac6ab23cb007970cd0e2263908d3d15a59be

commit 5207ac6ab23cb007970cd0e2263908d3d15a59be
Author: Wan-Teh Chang <wtc@google.com>
Date: Thu Aug 09 22:19:06 2018

Roll src/third_party/libaom/source/libaom/ e96c7350a..9655bde9f (1 commit)

https://aomedia.googlesource.com/aom.git/+log/e96c7350ab1e..9655bde9fba5

$ git log e96c7350a..9655bde9f --date=short --no-merges --format='%ad %ae %s'
2018-08-04 wtc read_tile_info: Validate context_update_tile_id.

Created with:
  roll-dep src/third_party/libaom/source/libaom
R=johannkoenig@google.com

BUG:  871928 
BUG:  oss-fuzz:9720 
Change-Id: I2ab7faaffc7763ae2cc29c2ee70ae6b3a70c2ca0
Reviewed-on: https://chromium-review.googlesource.com/1168148
Reviewed-by: Johann Koenig <johannkoenig@google.com>
Cr-Commit-Position: refs/branch-heads/3497@{#522}
Cr-Branched-From: 271eaf50594eb818c9295dc78d364aea18c82ea8-refs/heads/master@{#576753}
[modify] https://crrev.com/5207ac6ab23cb007970cd0e2263908d3d15a59be/DEPS
[modify] https://crrev.com/5207ac6ab23cb007970cd0e2263908d3d15a59be/third_party/libaom/README.chromium
[modify] https://crrev.com/5207ac6ab23cb007970cd0e2263908d3d15a59be/third_party/libaom/source/config/config/aom_version.h

This bug has been closed for more than 14 weeks. Removing security view restrictions.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot