Malicious PDF — malware analysis report

Static analysis result for SHA-256 774bb4c920c8c2ed…

MALICIOUS

PDF

42.1 KB Created: 2020-08-21 08:02:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b5706252f639c0ff46005609a5691e21 SHA-1: fbc156786f24776661aa4bdf40c287ffa145f731 SHA-256: 774bb4c920c8c2ed662e24ed94f4a9a7c8c125bf98a9964307964832904f94f2
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a link that redirects to malicious infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body, though heavily obfuscated, contains text suggesting a lure for 'free sheet piano let it go'. The PDF also hosts a large number of external links, many pointing to benign Shopify URLs, but the primary malicious link is the redirector. No scripts were extracted, but the presence of a malicious redirector suggests an attempt to download a second-stage payload.

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.cc/pify?keyword=free+sheet+piano+let+it+go
    • http://files.stjamesbands.com/uploads/1/3/0/9/130969373/2502521.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0429/9508/9559/files/22900477254.pdf
    • https://cdn.shopify.com/s/files/1/0450/3266/9334/files/psat_practice_test_1_answers.pdf
    • https://cdn.shopify.com/s/files/1/0434/8110/4541/files/91516183026.pdf
    • https://cdn.shopify.com/s/files/1/0440/5772/3030/files/53847048798.pdf
    • https://cdn.shopify.com/s/files/1/0428/4442/2310/files/nimesenuvekabovavo.pdf
    • https://cdn.shopify.com/s/files/1/0429/7555/9829/files/15667398240.pdf
    • https://cdn.shopify.com/s/files/1/0439/7318/1598/files/chhath_puja_song_2019_free.pdf
    • https://cdn.shopify.com/s/files/1/0433/4652/6376/files/mapoberuled.pdf
    • https://cdn.shopify.com/s/files/1/0432/2125/4312/files/76327955253.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/kepikopu.pdf
    • https://cdn.shopify.com/s/files/1/0434/6868/5464/files/kosimozudejo.pdf
    • https://cdn.shopify.com/s/files/1/0432/3350/9534/files/diderusalimupusozumepixo.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000067f9.bin
bcf805a7a08e133a7d87cb13276e0d7212216faa1b594cb3688db3f98e743d37
pdf-font-stream PDF embedded font (sfnt) at offset 0x67F9 5036 bytes
font_01_sfnt_off0000791b.bin
daf854dc189d1bd0845b449e37fe2b1263fc9c8bf1f9b415022c189feceb696f
pdf-font-stream PDF embedded font (sfnt) at offset 0x791B 10036 bytes