Malicious PDF — malware analysis report

Static analysis result for SHA-256 43512a9d65f6054c…

MALICIOUS

PDF

85.6 KB Created: 2021-04-14 23:09:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 3f18c4af7e99a1320ec133ddb0af7cc3 SHA-1: 691b2a8926a705cc07cf6f4589ac71acc9ac3dd2 SHA-256: 43512a9d65f6054cc0a526e6d137b1d0c4736b6529426b81ce3dc2b7b83ab2d4
126 Risk Score

Malware Insights

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

The PDF file contains an embedded URI pointing to a suspicious domain, identified as a link farm on disposable hosting. This suggests a phishing or malware distribution attempt, likely masquerading as a driver download. The ML classifier and ClamAV detection strongly indicate malicious intent. No scripts were extracted, but the presence of external URIs is a primary indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • 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 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://vilenefex.ru/strik?utm_term=hp+laserjet+4050tn+driver+download PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4406191/normal_6002d0d5779fa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499995/normal_600d794fa96e8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455881/normal_602ef1a4d9901.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376372/normal_600b70f81e403.pdfIn PDF document text
    • https://wuremude.weebly.com/uploads/1/3/2/8/132815206/fabidufe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415327/normal_5fd793717650a.pdfIn PDF document text
    • https://vanazufir.weebly.com/uploads/1/3/2/7/132740694/zevoze.pdfIn PDF document text
    • https://lidafeli.weebly.com/uploads/1/3/4/6/134683499/8d761efb52.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4445743/normal_6007d2a18e22f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368492/normal_602a085d13816.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://2065f6f1-29fb-48ac-a230-4f4ab2d4b746.filesusr.com/ugd/b62953_38971e0bbe1943b995b9636bc50e7390.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mukutud/how_do_you_fix_a_preparing_automatic_repair_loop.pdfIn PDF document text
    • https://f8340159-69ce-4309-ac43-521e9a8475b4.filesusr.com/ugd/bc0b97_e417ddb7f6d04991a78a98a329772b67.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/sosupejuxofedo/south_african_drinking_water_quality_guidelines.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c757256c-23e0-4601-80d7-a48d546a87d8/judivimatun.pdfIn PDF document text
    • https://f78a7b13-e75c-4ddc-9f3c-03cd83736f6c.filesusr.com/ugd/90c53f_9a9c77682fa14bed897dd147eb2941d7.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/pibabopuduj/bihar_police_si_syllabus_2019.pdfIn PDF document text
    • https://72b50e20-f79f-40ca-96b4-24bef83e308f.filesusr.com/ugd/1a1092_fb0e3e86671c40d9bc767eb91822eb6d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/adea5967-6e5a-4f2b-bbf0-b067042c7e5a/timber_tuff_chain_sharpener_cs-bwm.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/527989af-75f5-499f-b92c-dfed49da9a54/campos_de_la_psicologia_industrial.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/490a1339-3bcc-4a93-9c20-c11c2ce05999/buvixunerofubewenano.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c69cf87f-0e01-4e73-a560-9410e9cb34f7/pubobolusuludinajoja.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00012793.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x12793 20040 bytes
SHA-256: 0c3a632ad3c058f239a312101712ca0ba00ee88b05515f200866fb336c9786cb
font_00_sfnt_off0000f122.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF122 5496 bytes
SHA-256: c46b35da14dbda606f137d1341281f4cad5197fb148aeb4ed4054995baae9ad1
font_01_sfnt_off000103f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103F9 10328 bytes
SHA-256: 996e34e0a4746c8f521d54b48050eea0f0c3107f6c2694653f588a9850dfea11