Malicious PDF — malware analysis report

Static analysis result for SHA-256 40a11a155c83ecb3…

MALICIOUS

PDF

41.3 KB Created: 2020-08-16 22:25:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 087eb093cb150ca4e486bc02d8775c9a SHA-1: 19f37b0d4926bf3e62487dc28ec228f3dab95a23 SHA-256: 40a11a155c83ecb31e0e484294455dc7e69c6deabe9b2b4ac778ae5eda185fc3
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF document exhibits characteristics of a link farm, with numerous embedded URLs. One URL, 'https://ttraff.com/pify?keyword=icao+annex+3+pdf', is flagged as a malicious redirector. The ML classifier also strongly indicated maliciousness. The document body contains garbled text and metadata suggesting it was generated by wkhtmltopdf, a tool sometimes used to create SEO-optimized PDFs for malicious purposes.

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.com/pify?keyword=icao+annex+3+pdf
    • http://wekur.passion4healing.club/uploads/1/3/0/7/130740221/f9a340.pdf
    • https://cdn.shopify.com/s/files/1/0428/0002/1667/files/adjektivdeklination_bungen_b1_mit_lsungen.pdf
    • https://cdn.shopify.com/s/files/1/0435/0273/1430/files/betta_fish_fighting_videos.pdf
    • https://cdn.shopify.com/s/files/1/0437/0595/8553/files/thermodynamics_an_engineering_approach.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/19941062624.pdf
    • https://cdn.shopify.com/s/files/1/0429/7526/4924/files/74711508566.pdf
    • https://cdn.shopify.com/s/files/1/0432/2004/1886/files/walile.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/pifafesilepobusofamut.pdf
    • https://cdn.shopify.com/s/files/1/0438/2962/4982/files/define_conformational_isomers_in_chemistry.pdf
    • https://cdn.shopify.com/s/files/1/0429/0890/9734/files/65405379060.pdf
    • https://cdn.shopify.com/s/files/1/0431/8239/1451/files/56146081518.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
stream_005_off00007a97.bin
ca60383ca36372b019ccf49f7117f959f068646aa1553aa37d02374e057a01d2
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x7A97 18668 bytes
font_00_sfnt_off000046f4.bin
036afad5d7d22dde215f7245921f3c72481943f778c4d1dffe7f38ea6c13ce81
pdf-font-stream PDF embedded font (sfnt) at offset 0x46F4 5012 bytes
font_01_sfnt_off00005815.bin
b5f4525d9b0161f668e3b58da584a042ccfc5c15cd50e8db3c156bb5355765c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x5815 10040 bytes