OS Credential Dumping: Proc Filesystem T1003.007

Tactic: Credential Access

Adversaries may gather credentials from the proc filesystem or `/proc`. The proc filesystem is a pseudo-filesystem used as an interface to kernel data structures for Linux based systems managing virtual memory. For each process, the `/proc/<PID>/maps` file shows how memory is mapped within the process’s virtual address space. And `/proc/<PID>/mem`, exposed for debugging purposes, provides access to the process’s virtual address space.

Authoring guide

Patterns shared across the 5 rules above: which fields they filter on, what specific values they look for, and what they exclude. The catalog normalizes field names across vendors so Sigma's Image, Elastic's process.name, and Splunk's process_name collapse into one row. Each rule contributes at most once per row.

Fields filtered most (6 distinct)

The fields most rules look at when detecting this technique. The How column shows the operators authors use (eq, wildcard, regex_match, match) and how often each appears. Sample values are concrete examples to start from, not an exhaustive list.

FieldRulesHowSample values
EventType4in 4exec, exec_event, ProcessRollup2, start
host.os.type4eq 4
process_name4eq 2, in 2cat, egrep, awk, fgrep, gdb
event.type3eq 3start
process.args3in 2, starts_with 1, wildcard 1--pid, -eo, -p, /proc/*/maps, /tmp/
CommandLine1wildcard 1/proc/*/mem

Top indicator values (26 distinct)

Specific (field, operator, value) combinations the rules check for, ranked by how many rules under this technique use each one. The Corpus reach column counts how many rules across the entire catalog (any technique) check the same combination. High numbers point to widely-used indicators that are likely noisy on their own; combine them with another condition for useful signal. Blank means the combination is specific to rules under this technique. Click a value to expand the rules under this technique that use it.

FieldKindValueRules (here)Corpus reach
EventTypein
exec
4171
EventTypein
exec_event
4139
EventTypein
start
4134
EventTypein
ProcessRollup2
3117
EventTypein
executed
388
EventTypein
process_started
374
event.typeeq
start
3606
process_namein
cat
223
process_namein
egrep
211
process_namein
fgrep
28
process_namein
grep
214
process_namein
less
211
process_namein
more
211
process_namein
tail
28
process_namein
awk
113
CommandLinewildcard
/proc/*/mem
1
process.argsin
--pid
1
process.argsin
-eo
1
process.argsin
-p
12
process.argsin
command
1
process.argsin
pid
1
process.argsstarts_with
/tmp/
14
process.argswildcard
/proc/*/maps
1
process_nameeq
gdb
14
process_nameeq
ps
1
process_nameeq
strings
13

Exclusions (12 distinct)

Field/operator/value combinations excluded by rules under this technique (top-level not() clauses), sorted by how many rules exclude each. These are the false-positive paths the community has learned to filter out. A new rule that ignores the high-count entries here will likely fire on the same noisy paths. Click a value to expand the rules under this technique that exclude it.

FieldKindValueRules excluding
CurrentDirectorywildcard
/opt/Tanium/TaniumClient/*
1
CurrentDirectorywildcard
/opt/traps/deb-installer
1
ParentImagein
/opt/secl/linux-ir-scripts-v3/thieves.sh
1
ParentImagein
/opt/traps/rpm-installer/setup.sh
1
ParentImagein
/sbin/chkrootkit
1
ParentImagein
/usr/sbin/chkrootkit
1
ParentImagewildcard
/home/*/sunlight/thieves.sh
1
parent_process_nameeq
uac
1
process.parent.argsin
./uac
1
process.parent.argsin
/sbin/chkrootkit
1
process.parent.argsin
/usr/bin/finalrd
1
process.parent.argsin
/usr/sbin/chkrootkit
1

Rules under this technique

Every rule in the catalog tagged with this technique, grouped by vendor. Click a rule title for its full predicates, exclusions, and indicators.

Platform (all)
Domain (all)

Elastic 5 rules