Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c39ae1ec8b13475…

MALICIOUS

PDF

53.6 KB Created: 2020-06-01 19:57:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d51a92029fddb6a690c788879469eacd SHA-1: 026ddc69979672b2937bb0f029a6b2e064b27945 SHA-256: 4c39ae1ec8b13475b6a17daf02614a0eddfc8c7b5f3528fe6882b6b60e16bff5
94 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to SEO-optimized PDF files on various domains. This pattern is indicative of a link farm or redirection scheme designed to funnel users to malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious attack pattern. No scripts were extracted, limiting the ability to determine specific payload delivery mechanisms.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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 http://washingtonstatehealthadvocates.com/uploads/1/3/0/4/130483478/130483478.html#clonixinato+de+lisina+dilucion
    • http://lexusconcretellc.com/uploads/1/3/0/7/130776322/gosiso.pdf
    • http://triadedistribuidora.com/uploads/1/3/1/3/131384071/kogufamojexo-xidesisubevuse.pdf
    • http://theresachurch.yoga/uploads/1/3/1/1/131164112/sotogena_jopuxarulibesok_kevituli.pdf
    • http://jp-photopro.com/uploads/1/3/1/3/131383657/jikunofebaderal.pdf
    • http://4sapservices.com/uploads/1/3/0/2/130291350/8661895.pdf
    • http://storytellersforum.com/uploads/1/3/0/7/130775027/jidinazo_nisisetimamaf.pdf
    • http://74-123-73-44.mgwnet.com/uploads/1/3/0/3/130379596/9e66a.pdf
    • http://washingtonstatehealthadvocates.com/uploads/1/3/0/4/130483478/terms.html
    • http://washingtonstatehealthadvocates.com/uploads/1/3/0/4/130483478/dmca.html
    • http://washingtonstatehealthadvocates.com/uploads/1/3/0/4/130483478/policy.html
    • https://pepavujewow.files.wordpress.com/2020/05/36944511685.pdf
    • https://difomanonis.files.wordpress.com/2020/05/pudunej.pdf
    • https://noweposojif.files.wordpress.com/2020/06/vatozejanawakifibodugo.pdf
    • https://porugisi.files.wordpress.com/2020/05/74436517788.pdf
    • https://fupalowonega.files.wordpress.com/2020/05/5383344235.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00008e83.bin
1beaa280cacaf9ba6d9fcf1f94b1e5f01d4d3f6e802884e63ee50acb243f7832
pdf-font-stream PDF embedded font (sfnt) at offset 0x8E83 11948 bytes
font_01_sfnt_off0000b4f3.bin
c988415812f594187b0a0ed75dc52802e798e1695b49bd300f8412a65040a449
pdf-font-stream PDF embedded font (sfnt) at offset 0xB4F3 16204 bytes