Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb86e953fd405b02…

MALICIOUS

PDF

76.7 KB Created: 2021-07-13 17:05:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 556de3be618b0e2044a87d795ce86280 SHA-1: 72df70fca7f177211665ac97b12b282f25c36c9b SHA-256: cb86e953fd405b02676be904d9422d8b4cd7f29c3ed0ae5ee48f38ec370238c9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous external links, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution through these links. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the link farm heuristic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://ntiverification.com/userfiles/file/ratirudopew.pdf
    • http://bakerfamreunion.com/clients/1/13/13be4b03bdabdd3a133c3ee64ed6201b/File/kerugelazoxavowekapuv.pdf
    • http://jeyadhurgatemple.com/userfiles/file/nuzikuwuduvaponajutabefeb.pdf
    • http://ginzaoakland.com/uploads/files/81239368098.pdf
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/39aa9a9d7854abd60c8cf2974e1789af/tiseduzeroputinuxuxurizam.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607262d035065---76040932497.pdf
    • https://oxi-dental.ro/imagini_ws/pavanodikemaruxi.pdf
    • http://hengtaixin.com/HangShun/ckfinder/userfiles/files/papimisibupega.pdf
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160ddbcec7d45f---leruped.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/e117d317c16d927810e6ae728205c4fa/dujed.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d06947923af---gugizoxuvovakus.pdf
    • http://cz-synergy.cz/data/file/visatugux.pdf
    • http://metapolar.hu/tmp/leregolalojikuzexewinu.pdf
    • http://eksan-ltd.com/userfiles/file/dazonoparosu.pdf
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/160be7ad12d7f6---15372454686.pdf
    • https://cleanenergy.mn/uploads/files/66659514088.pdf
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ce9c1ada54---44786545868.pdf
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bb91c24248b---92921517591.pdf
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086202566a19---xotakajivuxopupoxon.pdf
    • http://kasystemofkarate.com/clients/861259/File/satimabijolokaxuwuxu.pdf
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/35106286277.pdf
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608d6eb0b0233---20839307625.pdf
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/54106764170.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=indian+nepalese+food+near+me
    • 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_off0000c9fb.bin
efb2f5feace402a46dcfdacbcf78d6e7244ce3adf486bf3e92a130d6665d468e
pdf-font-stream PDF embedded font (sfnt) at offset 0xC9FB 16992 bytes
font_01_sfnt_off0000f5aa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5AA 16792 bytes
font_02_sfnt_off00010dc1.bin
df17526bcf5737f4fbf7aed339e8bc187f7ecd32e1765c8a02ccabecb84a1386
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DC1 10512 bytes