Malicious PDF — malware analysis report

Static analysis result for SHA-256 5801e814867f2dd0…

MALICIOUS

PDF

9.4 KB
MD5: a91f13f6f1bc6b89b1e30085e7ce1f0b SHA-1: cf4bee383b3c1b547fdaabe548499cee82e2e64b SHA-256: 5801e814867f2dd0ab146e6d257177e671dfe04b756d008b23e81b65bf9dd950
266 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/Shell T1204.002 Malicious Link/URL T1071.001 Web Protocols

The PDF file contains embedded JavaScript that is heavily obfuscated and utilizes `eval()` and `unescape()` functions, indicating malicious intent. The critical heuristic 'CVE_2007_5659: Collab.collectEmailInfo' points to a known vulnerability exploited by this PDF. The script likely acts as a stager, downloading and executing a second-stage payload. The absence of readable document body text means the exact lure cannot be determined, but the exploit itself is clear.

Heuristics 9

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-35912 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35912
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • Annotation subject callee-key hex JavaScript stager high PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER
    PDF JavaScript uses syncAnnotScan()/getAnnots() to read an indirect annotation /Subject stream, percent-decodes it through marker replacement, then uses a callee.toString()-derived key to decode and eval the final exploit stage.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
7218a1c68060953321573daa035b16f5f32928ce25a9eb656690dbe78cd9464e
pdf-javascript-stream PDF /JS object 7 at offset 0x19B 201 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
annotation_subject_callee_hex_stage_000.js
56d817efb0f7ba236ffccf5f8f94fe15ef26decf766b590d20110c1e4053ecee
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5153 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
ba77e7371f06962de100215623694ff176a98ca7ed47fb1add23449eda6eeafa
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2B5 12133 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
deobfuscated.js
df98704763c962ae9976592207519b0d693d6a7ed48022eefb5d223fafde2624
deobfuscated-js PDF JavaScript deobfuscation pass 43654 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 4 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).