Malicious PDF — malware analysis report

Static analysis result for SHA-256 663bb60c611426f2…

MALICIOUS

PDF

74.8 KB Created: 2021-08-26 19:35:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1fd6e0b79866e7dc98be6b9730a4ef66 SHA-1: 0356f1377b55863cd5c8d9d14b2a0d389035db47 SHA-256: 663bb60c611426f271049dbd0bde181b6ae4b961231984688863c63d0ac0192a
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, specifically flagged as 'Pdf.Phishing.Trojan'. Heuristics indicate it functions as a link farm, directing users to multiple compromised or disposable hosting sites. The document body is heavily obfuscated and unreadable, suggesting it's not intended for human consumption but rather to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://centrosteadycam.it/wp-content/plugins/super-forms/uploads/php/files/2d6fec564394771d808ba0262edb1dad/wuniwivosozatude.pdf
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd9e629062e---78972478288.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160788f02abc71---89756179258.pdf
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/3l8p7ihgti8j26efcej7r8490i/zupafurelukulejiwitetub.pdf
    • https://ce-mi.pl/uploads/userfiles/files/39791122378.pdf
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/9868290f64904aec885e8d8632940503/zasugoguwoso.pdf
    • https://editora-arara-azul.com.br/site/admin/ckfinder/userfiles/files/wepelogu.pdf
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/9727q5s0pevococj5hlrvra7o4/9186793034.pdf
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2fbbc5a7ca---49473780035.pdf
    • https://safrano.pl/userfiles/file/44692944905.pdf
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611fec40e43f0---51468846244.pdf
    • https://audreyheselmans.com/_files/file/82043649929.pdf
    • http://pivotal-technologies.com/userfiles/file/rutim.pdf
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/160f4d2cf7e6f5---nuwepevivodewikutapopenad.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/a6jhdo0gmv3qqf39tnrdfjuhbm/nitevok.pdf
    • https://vitecolte.shop/file/32874464234.pdf
    • http://shacklefordlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nokimigarafosepow.pdf
    • http://zgkimsteszew.pl/img/upload/files/xoxujifebilesijudelixofi.pdf
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096012f02571---dadipolaxejepo.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cab614b60a---60301196331.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/84925945f291ae4fad260cea9f4c3039/87132508716.pdf
    • http://jfe.hk/userfiles/92699353057.pdf
    • http://abwessex.com/uploads/files/79767565819.pdf
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160da532a13287---xuvedez.pdf
    • http://t-eamplus.de/web/editor/files/funimiluzujab.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=extra+luv+mp3
    • 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_off0000c20b.bin
9f62d415081030d9e090c19a789497bf5259cf386189de65374e5af5f7a3a77f
pdf-font-stream PDF embedded font (sfnt) at offset 0xC20B 16216 bytes
font_01_sfnt_off0000ec4a.bin
e197814b2a59b12ab25d3f482cbfb92369911dc31c533118b56af2ce301d3e11
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC4A 10220 bytes
font_02_sfnt_off00010346.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10346 16792 bytes