Malicious PDF — malware analysis report

Static analysis result for SHA-256 c790898dad32a733…

MALICIOUS

PDF

52.5 KB Created: 2020-08-23 01:13:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 18e4d70f73aeeb1be51f22e9919f50ec SHA-1: 6dd80ab10fe7c000ce8d874a6e51e6adeac4f283 SHA-256: c790898dad32a733d83cb0cb86ecb01112f98563c8ee5fb661217498bac3898e
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains embedded links that point to a known malicious redirector, disguised with keywords like 'bookkeeping excel template small business'. The ML classifier strongly indicates maliciousness. The document body, though heavily obfuscated, also contains the malicious URL. The presence of multiple embedded links to external PDFs, some of which are benign and others unknown, suggests a link farm or redirection strategy to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.ru/pify?keyword=bookkeeping+excel+template+small+business
    • http://duwujuja.bgiapartments.com/uploads/1/3/1/6/131606289/pesizu.pdf
    • https://cdn.shopify.com/s/files/1/0434/4909/0200/files/succubus_south_park.pdf
    • https://cdn.shopify.com/s/files/1/0436/4160/2198/files/56170701877.pdf
    • https://cdn.shopify.com/s/files/1/0432/9324/5590/files/zosasedezefubisuluzaji.pdf
    • https://cdn.shopify.com/s/files/1/0434/1514/2551/files/15055700040.pdf
    • https://cdn.shopify.com/s/files/1/0447/6190/7351/files/fun_facts_about_the_bible.pdf
    • https://cdn.shopify.com/s/files/1/0429/6186/2810/files/47765217230.pdf
    • https://cdn.shopify.com/s/files/1/0430/9994/7169/files/10805510113.pdf
    • https://cdn.shopify.com/s/files/1/0434/5580/7640/files/calzedonia_katalog_2020.pdf
    • https://cdn.shopify.com/s/files/1/0429/8375/1831/files/ragurerowewojaremefogo.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000081c6.bin
922a52ade2db9cac60001a08231355e89a164c758fb0e2f489485ccf1ba53f83
pdf-font-stream PDF embedded font (sfnt) at offset 0x81C6 5360 bytes
font_01_sfnt_off000093f1.bin
ac840b22555232f8a344629fb2c8ddbce5859b9f868e58f040acccd6332b1c2b
pdf-font-stream PDF embedded font (sfnt) at offset 0x93F1 10384 bytes
font_02_sfnt_off0000b750.bin
a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f
pdf-font-stream PDF embedded font (sfnt) at offset 0xB750 4324 bytes