Malicious PDF — malware analysis report

Static analysis result for SHA-256 a57f399a52c967f3…

MALICIOUS

PDF

78.3 KB Created: 2021-03-23 23:47:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 351ffbe01654b52a2419f4e49399cb6e SHA-1: bd07a2bb51adec913ba9d5cb2c6f06b2bb87bd2a SHA-256: a57f399a52c967f39629b424374981284f2447ceff50253e6018ef7a2bf65b97
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous external URLs point towards an attempt to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://xajibur.ru/123?utm_term=adrenal+carcinoma+guidelines PDF link annotation
    • http://agent-ritual495.online/speakeasy_meaning_in_russian3hoxc.pdfIn PDF document text
    • http://tesocoin.online/merchant_of_venice_ebook_download6sp5f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368781/normal_6022c5239dba0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4412591/normal_60081bd8de102.pdfIn PDF document text
    • https://zupuluduwiwafop.weebly.com/uploads/1/3/2/6/132681460/baturikikus.pdfIn PDF document text
    • http://biotringel.shop/loguremekogezalidoluduee5q4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375907/normal_60551e19dff99.pdfIn PDF document text
    • http://chambreapp.xyz/fibigan6bec6.pdfIn PDF document text
    • https://kabosasano.weebly.com/uploads/1/3/5/3/135398154/detilure-bifosuj.pdfIn PDF document text
    • http://eushopvmn.site/pasowisivulupikajumohsenp.pdfIn PDF document text
    • https://tivaxuxilo.weebly.com/uploads/1/3/4/1/134131375/lipidavepokovut.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446162/normal_6054abb322b95.pdfIn PDF document text
    • https://dexidexida.weebly.com/uploads/1/3/4/2/134235246/wujep_zibiniz.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485926/normal_601dd0d0495f6.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://91e55214-10ad-44cf-a10a-60a9392df58b.filesusr.com/ugd/e1c37d_f1bba757250e4636b2550d1e2d763d36.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/kagedatabujo/breakdown_english_movie.pdfIn PDF document text
    • https://d497f082-4895-42de-a72c-038d9367c8a3.filesusr.com/ugd/8e727b_393f1439c5de4e088e25672bcf5c37d6.pdf?index=trueIn PDF document text
    • https://0926596c-b1e6-4473-87d6-fed2e709bfeb.filesusr.com/ugd/e2a635_52aa4e0353664570b39cf7db7fe39988.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/gulapore/lijikov.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
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f799.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF799 5248 bytes
SHA-256: ae509e9858e14b3eb035dbf36832c587662cd19869c70a1bb72b9d712ed852ad
font_01_sfnt_off0001095a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1095A 10184 bytes
SHA-256: e07ab68c0017844c47aaab9c2978f122fff169693f64d532ff18d065da4a7b1d