Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca40353d54094ebb…

MALICIOUS

PDF

38.0 KB Created: 2020-04-11 15:27:45 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6) First seen: 2020-09-04
MD5: 1b0137cac2d8d4c6749c8a34ca1aa52a SHA-1: 5239b9b352b0124a2941b4519c55f4184ce66715 SHA-256: ca40353d54094ebb2e2f604dee552bb947e5134be60de2700362f0b7d5ed5fd6
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a significant number of external links to other PDF documents hosted on various domains. This behavior is indicative of SEO poisoning or a link farm, designed to drive traffic to these external resources. The ML classifier strongly flagged this PDF as malicious, supporting the suspicious nature of the numerous external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://mmhac.com/uploads/1/3/1/6/131636664/131636664.html#zenspirations+dangle+designs PDF link annotation
    • http://sophiamason.org/uploads/1/3/0/9/130969214/1d4957f7.pdfIn PDF document text
    • http://stillchampion.net/uploads/1/3/1/1/131164273/1763889.pdfIn PDF document text
    • http://enchantmentaesthetics.com/uploads/1/3/0/6/130604509/7931202.pdfIn PDF document text
    • http://coloradopallet.com/uploads/1/3/1/4/131411600/dodazonupeteduj.pdfIn PDF document text
    • http://snarkytwist.com/uploads/1/3/0/5/130588494/2953286.pdfIn PDF document text
    • http://azbnk.com/uploads/1/3/1/3/131398108/wulojapupode-dudajetapel-rebutem.pdfIn PDF document text
    • http://domterapii.com/uploads/1/3/0/5/130551882/57e73ed82953.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006809.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6809 9516 bytes
SHA-256: 3fddaaba875fd92c5981c759eb53bc6460d8baeefebe13812e3cb63ecdfc68a9