Malicious PDF — malware analysis report

Static analysis result for SHA-256 b46f3b4a7078c1f6…

MALICIOUS

PDF

83.5 KB Created: 2021-06-30 07:08:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d99ccb14b43e5278832156ae8caecbb5 SHA-1: b0e7e56670c98369c683f78b809b0a801393db15 SHA-256: b46f3b4a7078c1f6b14bab83dc5db0cfe56f1498fb29f192629910af34949b7a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The embedded URLs and the nature of the heuristics strongly indicate a spearphishing attachment delivery vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://xn--b1akwe.xn--p1ai/userfiles/file/85384670764.pdf
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16088be9b5082b---xasavenek.pdf
    • http://studioingegneriavaragnolo.com/userfiles/files/45383487656.pdf
    • http://www.annaleehuber.com/content_files/file/bikutenefafelubis.pdf
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/lj93n627k2ltbpcsm1gpaodg46/56232522329.pdf
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/i55e70tioouvnhsr2ju43t2q19/pazuvixemifitexugefemuf.pdf
    • https://thuaphatlaihanoi.net/uploads/files/1632652908.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/529b9be60270d2e2d04ee3cb8b19a9ec/79920715351.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160b3f7050b665---2328065188.pdf
    • https://jxloanchien.com/style/postimage/file/rewinitusorowitixo.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a0f994b4cf---10002875613.pdf
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078de467705a---mazerujizekavux.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160bfc46e75172---wazuzalunaka.pdf
    • http://urparitet.ru/admin/ckfinder/userfiles/files/69077180425.pdf
    • http://burelomdo.com/ckfinder/userfiles/files/41119820046.pdf
    • http://otoozevran.com/resimler/files/46674297856.pdf
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd21cc9040---65034491795.pdf
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/nvmq5egu8qfsndi5h1n2e9iok4/18998623453.pdf
    • https://hotelmitrutarija.com/uploaded/files/61060093169.pdf
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8cbb4d56f2---tolobisusakewelever.pdf
    • http://albatrossmrn.com/konadnew/userfiles/file/vidopu.pdf
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f54619013b---junukipaguzadinibojax.pdf
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/2pipm9008miskoiuu4hllg22ds/52743444741.pdf
    • http://edu-family72.ru/content/images/uploads/file/96265387204.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=nancy+drew+mystery+stories+the+hidden+staircase
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e0ab.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0AB 16792 bytes
font_01_sfnt_off0000f8bd.bin
fb7d5d320df9c80ceaa04c82474305a14371e742a11139c6ac4d752758928deb
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8BD 17268 bytes
font_02_sfnt_off000125f2.bin
9bc45e37faa2e297c19fa0b00f559f3d991e88f2ab58e6368cfd224199c2358e
pdf-font-stream PDF embedded font (sfnt) at offset 0x125F2 10764 bytes