Malicious PDF — malware analysis report

Static analysis result for SHA-256 6711db6ab0a84634…

MALICIOUS

PDF

99.6 KB Created: 2021-07-31 12:45:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1c3a2a17827162f227db268768f08910 SHA-1: 0bac483722108f75664b4c6379e64c4638eb7ac4 SHA-256: 6711db6ab0a846342cce6f3a3be570d04c885d5b6789e0a1a25da850459189ed
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to compromised WordPress sites and other disposable hosting, forming a link farm designed to trick users into downloading files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the heuristic findings and URL analysis point to a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://www.rosabrockenhaus.ch/ckfinder/userfiles/files/kupuvadejozavawimu.pdf
    • https://yourownadviser.com/ckfinder/userfiles/files/kavixamapakedoludu.pdf
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/0d9cc294bfa732e9835867070e571653/bajikametijos.pdf
    • http://sequirk.ie/userfiles/file/70525285994.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1606f9fd8ea758---zafivosodek.pdf
    • http://zrdb-drogbud.pl/Upload/file/masuzuvagixuxobofen.pdf
    • https://seerupit.dk/assens/file/wirivepuf.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d69aceade12---rumuzu.pdf
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/6db82875a85867880634489326789e28/16410451589.pdf
    • https://rockdental.co.uk/wp-content/plugins/super-forms/uploads/php/files/875f636fa9da976ec70a7b7419bc13b1/3234902337.pdf
    • http://apexibd.com/uploads/fck_uploads/file/39085706061.pdf
    • http://gpmpoolandspa.com/ckfinder/userfiles/files/62719639635.pdf
    • http://asesorgubernamental.com/images/file/venilesazizojex.pdf
    • http://portableandcool.com/files/files/53463689396.pdf
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cdb8c3c9f5---jakasukewo.pdf
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/16099cfc238cdb---gimadekomodi.pdf
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/89929ab991c0734c6f9a42bf5085a61a/29428358094.pdf
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/fc4a11ce689f3f31a93ea4243176c848/74198789258.pdf
    • http://waukeganeast1980.com/clients/877304/File/84022008941.pdf
    • http://www.celso.org/download/6923998101.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/ge34r34iab9o7vhqlkavo6juue/21537285204.pdf
    • https://www.ppmcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/2nrivio1v3vb5biapj4kbqkcir/kosetuxiwetis.pdf
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/1ea5fad7db9493e86f5776573a912b98/kofexafesuzurukapajije.pdf
    • https://coil.hk/upload/files/wiwoj.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=offer+letter+format+for+software+engineer+doc
    • 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_off00011f6a.bin
980e7d026a3a2f1067ac070174562a43ab2ef7cfa14caf1cd60420255b91b5c5
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F6A 17972 bytes
font_01_sfnt_off00014efc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14EFC 16792 bytes
font_02_sfnt_off00016713.bin
6af1297ca134dc83e0f124e9c7619a72382310c97816a11c626ee1f8d8ab2db6
pdf-font-stream PDF embedded font (sfnt) at offset 0x16713 10932 bytes