Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4b587645ba9c018…

MALICIOUS

PDF

79.8 KB Created: 2021-08-28 13:26:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 63132b9e14aa7fa086cafce90894617c SHA-1: 107eda344f485b0ea54a73a62fc4462a380f16a7 SHA-256: d4b587645ba9c018b249a92395cc877613b45db85311d1a968b38426d0c8b5a7
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/8b9de7407f23580bff9ab3ee7ea22cff/76713559724.pdf
    • https://autoradiator.mn/uploads/ckfinder/files/zapufozi.pdf
    • https://dzido.pl/userfiles/file/wovusigexaruzivibedino.pdf
    • https://oilbasaro.com/web/images/ckfinder/files/20210611105408.pdf
    • http://ri-rm.ru/userfiles/file/poguloroxobukurifixexad.pdf
    • http://nt-module.ru/ckfinder/userfiles/files/456553716.pdf
    • http://win-sonic.com/ck_imgs/files/46337783841.pdf
    • https://rainbowfurnitures.com/files/files/37766292018.pdf
    • http://carlaschroyen.com/content_docs/12573669828.pdf
    • https://mszukam.pl/dat//file/6969151034.pdf
    • http://phonphangschool.com/upload/files/gavudofijoxenosegelibi.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/5mj6urkt27midrpqab26mt0fq7/zapuwiv.pdf
    • https://livre-art.com/ckfinder/userfiles/files/pidufaramubiwuvi.pdf
    • http://dobre-jaja.com/Upload/file/7209254502.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2b2416786---98159206796.pdf
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610cb758bb6d0---66145413060.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac3558ba6af---3660456664.pdf
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1609b11da922f0---89375633953.pdf
    • http://grafordexstudents.com/clients/0/05/05b3dbe7dd9dc6f92b523d2b721f2ffd/File/patirerovaneriredamomo.pdf
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e97f2a320af---45690550922.pdf
    • https://cerquilho.sp.gov.br/public/admin/globalarq/uploads/files/dojilamurazoborotesof.pdf
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/65cd478fb79f36c653e76679e9fb2aed/11857067427.pdf
    • https://xo-sound.ru/userfiles/file/65837541147.pdf
    • http://gopherandsquirrelcontrol.com/admin/images/file/87120149625.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=tamil+dubbed+comedy+movies+isaimini
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c7ae.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC7AE 16792 bytes
font_01_sfnt_off0000dfbb.bin
43c7763b346e6e943adfa1be4ed0749c175b6381940c7685d3827eb994a34161
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFBB 2332 bytes
font_02_sfnt_off0000e9da.bin
6c1b973ffab9c39e53be3bbcd90b5fe5fde0cc40edd931dd6a032e52c1b8c95c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9DA 17788 bytes
font_03_sfnt_off000117c6.bin
28c928c988eb4fd3300030be4403cad611d14594a6a814f82ebdf75ed82de149
pdf-font-stream PDF embedded font (sfnt) at offset 0x117C6 10716 bytes