Malicious PDF — malware analysis report

Static analysis result for SHA-256 8617dc79170097f5…

MALICIOUS

PDF

89.8 KB Created: 2021-06-30 19:17:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4f74b1ce4835c0482d569accfc1c0e83 SHA-1: 339f91c6375142d2d460710e594ac1f0f199d245 SHA-256: 8617dc79170097f553e5c022d6c14b8e4e86b7324ec3ce26394801473b7723ac
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites and utilize UTM parameters, indicating a likely phishing or scam campaign. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted, and the document body was unreadable, but the heuristic firings and numerous malicious URLs are sufficient evidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • 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://medvor.ru/uplcv?utm_term=paruthiveeran+hd+video+songs+download
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/6165fbe1a824ec8976ed37839b29f814/revadotosusawakimis.pdf
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/1d68a9a9132b5eaaa78ba8e6b56a1570/95953075530.pdf
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d46ed07b32e---gunediralotu.pdf
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1607955ba19132---60175322040.pdf
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dbc6804f477---nivekovogitixuzumefulu.pdf
    • https://alternativecarrepair.com/userfiles/file/gevakelezukelezexavale.pdf
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/8853f56760c0ec525fe62e624525c61d/dariwetusigiwegekerupovo.pdf
    • http://jcon-aps.dk/userfiles/file/tawoweseke.pdf
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/2ff8037e8fc9930371b6fae64814a60c/1897768383.pdf
    • http://sapaelitehotel.com/webroot/img/files/56901853084.pdf
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ad5b6170eef---65004635309.pdf
    • http://trimblehighalumni.com/clients/84492/File/gafakatenumirepas.pdf
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b515600c436---kesugimokozodolidilepudow.pdf
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083a38a14b33---806278681.pdf
    • http://emanuelmlevin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kexotofava.pdf
    • http://solmoda.it/userfiles/files/fakuvonanilemom.pdf
    • http://ghgunclub.com/clients/f/f3/f3036db30fa8ed97f94f648fc77c1040/File/5592236253.pdf
    • http://barcelonasixtytwo.com/userfiles/file/nilugiziz.pdf
    • https://olmitek.by/wp-content/plugins/super-forms/uploads/php/files/mtudepgsm6sgl2oats9a64dfc1/tolugagujixonokalezizafol.pdf
    • http://patriabrno.cz/userfiles/files/tonev.pdf
    • http://massimoandyuethui.com/clients/69227/File/tazepetowewuzabokinubon.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8e025d8d0---98219890308.pdf
    • https://vaitinhdien.com/app/webroot/upload/files/wenebalopulebe.pdf
    • 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_off0000fb4c.bin
10aee51474c02f96a4ff43c6c7acfd12d32ca78abf016e569b7094f29105e179
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB4C 17704 bytes
font_01_sfnt_off00012956.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12956 16792 bytes
font_02_sfnt_off0001416d.bin
82bd7d7c8b1711b1d4ae16e02ae5ae5679e75702949e3b8f1dd785c2987efc6b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1416D 10780 bytes