Malicious PDF — malware analysis report

Static analysis result for SHA-256 b081bd6ac7a190fa…

MALICIOUS

PDF

94.1 KB Created: 2021-07-16 06:37:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7ffac776effc292d29b23b6bafc3e4b6 SHA-1: f1d36353c9b258a899cda71ebeb5750e08b048dc SHA-256: b081bd6ac7a190fa0ce01b70070dca02627e81f34cebbc4904c8184a4bf9789c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to compromised CMS uploads and disposable hosting, indicating a link farm designed for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a phishing or redirection attack, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9941

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://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/o1lb6dtimfgjt7shp22a2eg4g3/16909948103.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160af85f9012f5---rulexoxedezatimozixogax.pdf
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/c7uco8ietva8o73fq770rumep3/27280594107.pdf
    • http://vivo-mebel.ru/upload/file/88344667197.pdf
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/ncjos60sdrvluljukja9gq22eo/tanepitibomewufiwesilod.pdf
    • http://iburgisidimarsala.eu/userfiles/files/rifaburiduzimavom.pdf
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/1f6d883e1e8e4587aff60cf4a2510217/gimanesitotifuxumiwibopu.pdf
    • http://kusadasidentalclinic.com/img/userfiles/files/wofavimof.pdf
    • http://darienhigh69.com/clients/866565/File/15380901287.pdf
    • https://giriconsultancy.com/content_files/files/60027416237.pdf
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c4b8500af28---32520564280.pdf
    • https://takeorders.online/wp-content/plugins/super-forms/uploads/php/files/17gf0hcpl1frmb73flcvga9g4e/39369962993.pdf
    • http://master-sign.ru/ckfinder/userfiles/files/sizibaxirixa.pdf
    • http://www.roosprommenschenckelfoundation.nl/ckfinder/files/files/81007156602.pdf
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/16094485f19be0---bafenajobegitux.pdf
    • http://ambulatorioveterinariocamali.com/userfiles/files/xabuwa.pdf
    • https://szabobuszberles.hu/files/files/judejibuvaki.pdf
    • http://premiercontractinginc.com/files/file/72589347770.pdf
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/049lslk0r8rf1edk4r4a80bsj6/solajunonos.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ecd13421c5---74612604053.pdf
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/548ffdc8de6656d5e99d7bd6ff632d7e/79988912514.pdf
    • http://smit-electronic.hr/upload/datoteke/zivebumi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=lewis+short+dictionary
    • 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_off0000f487.bin
aea51b588be5645c9201db9735cbdf4a83ddd0562dd1e4d440f207a456c199c5
pdf-font-stream PDF embedded font (sfnt) at offset 0xF487 10580 bytes
font_01_sfnt_off00010cc2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CC2 16792 bytes
font_02_sfnt_off000124cf.bin
478d64aad58a46c60a63c2bd6d05d9c39068b35528f549688063ac651822ff24
pdf-font-stream PDF embedded font (sfnt) at offset 0x124CF 1760 bytes
font_03_sfnt_off00012d26.bin
37de3a6bd81fa157511d6853925066434ba7da3bd38d10435fd4726ac8bd1388
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D26 26164 bytes