Malicious PDF — malware analysis report

Static analysis result for SHA-256 6682ba4de85fac96…

MALICIOUS

PDF

38.7 KB Created: 2020-04-13 07:33:04 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: a68f9f871a2eb99682104f33b6fc08ea SHA-1: 3d0e5eae458f03236a2214d97be44e4ee3fe3156 SHA-256: 6682ba4de85fac96a59d709e4bcd9b2f3d49e646d107b10094df02ab329b5f25
136 Risk Score

Malware Insights

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

The PDF contains a large number of external links to other PDFs hosted on various domains, indicating a link farm or SEO manipulation tactic. The ML classifier also flagged this PDF as malicious with high confidence. While no scripts were explicitly extracted, the presence of numerous external links suggests an attempt to redirect users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://jcmotorsport.org/uploads/1/3/1/3/131381840/131381840.html#wilson+blade+104+v7+vs+v6
    • http://landforsaleinlafayettecountyms.com/uploads/1/3/0/5/130551323/fifopem.pdf
    • http://flotamagdalena.co/uploads/1/3/0/5/130539676/nasokewadovilu_gejiju_loguvomuduzulin.pdf
    • http://jcwaterfloats.com/uploads/1/3/0/5/130541462/pezatolojixowidisog.pdf
    • http://unicornartisans.com/uploads/1/3/0/9/130969026/luwawumixalu-dikibudufa-gimofovuseb.pdf
    • http://walkercountymonuments.com/uploads/1/3/0/7/130738970/3724476.pdf
    • http://home-enhancements.shop/uploads/1/3/0/6/130604459/fijaji_kadut_zazuzerogupa_vusukitawedo.pdf
    • http://jr-group.org/uploads/1/3/0/2/130270845/wapodosuwu.pdf
    • http://oliveryouthsoccer.com/uploads/1/3/1/4/131407504/576601db4883.pdf
    • http://gvhomesolutions.net/uploads/1/3/0/3/130323400/e0a43c33.pdf
    • http://maryolshahad.com/uploads/1/3/1/4/131406291/sunifigegimit_xokumuxu_vakeb.pdf
    • http://creativbordum.com/uploads/1/3/1/4/131453969/legel.pdf
    • http://malawimountainbiking.org/uploads/1/3/1/3/131379168/2941325.pdf
    • http://myeasystudy.com/uploads/1/3/0/4/130483617/8009109.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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007259.bin
3efe3056438239ffe0c11ff10ad7ae3872892310f954440f2a700c7c0fa36413
pdf-font-stream PDF embedded font (sfnt) at offset 0x7259 7596 bytes