Malicious PDF — malware analysis report

Static analysis result for SHA-256 914a54d4fc0b755a…

MALICIOUS

PDF

76.8 KB Created: 2021-03-08 14:16:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 61fe569ca2748ed6193e902388fe0d1c SHA-1: 5774a1b0540059459390efee66de94ddce0877bf SHA-256: 914a54d4fc0b755a5caf1dbf2451ec792b7310872b0a61e9ae9602f34fd4fa4a
156 Risk Score

Malware Insights

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

This PDF document was flagged by multiple heuristics, including ClamAV and an ML classifier, as malicious. It contains numerous external links, suggesting a link farm or phishing attempt. The document body, though heavily obfuscated, implies a lure related to a 'company resignation letter'. No scripts were extracted, but the presence of external links indicates a potential for downloading further malicious content or redirecting to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://bologen.ru/award?keyword=company+resignation+letter+pdf
    • https://cdn.sqhk.co/kakapoxavu/hd3gfsF/42712006504.pdf
    • https://static.s123-cdn-static.com/uploads/4426945/normal_5ffbde340e8f7.pdf
    • http://sakhavto.ru/satanorujavy7zp6.pdf
    • http://jusukigib.sportsontheweb.net/i_pace_max_charge_speed.pdf
    • https://static.s123-cdn-static.com/uploads/4496225/normal_5fc826800e76e.pdf
    • http://zoluwofemofuper.sportsontheweb.net/56262071595.pdf
    • https://static.s123-cdn-static.com/uploads/4454547/normal_5fcd88e9ca99a.pdf
    • https://static.s123-cdn-static.com/uploads/4455881/normal_5ffbb46a276c9.pdf
    • https://cdn.sqhk.co/lunexubafexo/hfFSgfs/jekubifoxude.pdf
    • http://nuverlites.online/418661881551izx5.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://88966db1-4a83-4446-b941-f65022a6235f.filesusr.com/ugd/928e0f_a3b24c7dd024454ba2d7a48b19f34142.pdf?index=true
    • https://s3.amazonaws.com/wakuzidi/rezugumogeboginid.pdf
    • https://s3.amazonaws.com/makumapikeze/lego_worksheets_ks1.pdf
    • https://45180a89-8b92-4d54-a4c6-cdf0ad6af3c7.filesusr.com/ugd/2b98a3_dfe10ff4030c41ffae22d9c506b5390f.pdf?index=true
    • https://s3.amazonaws.com/neporezofov/gumegufutifofolinuzetet.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_off0000ef07.bin
9f251e178fa7bbb80081b7750e94d3b2e0990a335f7ef52077441aff7bdbbaa6
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF07 5368 bytes
font_01_sfnt_off00010138.bin
4f6b591a77dba9d080de718ebe6bc74816205f566963d8a303846a685ac64494
pdf-font-stream PDF embedded font (sfnt) at offset 0x10138 10804 bytes