Malicious PDF — malware analysis report

Static analysis result for SHA-256 f488dec68c15b578…

MALICIOUS

PDF

80.8 KB Created: 2021-08-16 04:46:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 237d85aa2b304105737652fd35547335 SHA-1: 6536cb7153cece0c16a0ae9b51d21bc840a4862f SHA-256: f488dec68c15b578c5bf1efff13987ae8090f597a3417898964eb0e775d2266f
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm, with many distinct hosts and URLs pointing to potentially compromised CMS uploads. The ML classifier and ClamAV also identified it as malicious, specifically a phishing trojan. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking readable content, but the presence of numerous links to external resources strongly suggests a phishing or malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/85e664b1858ce24b096a5472e00d972a/karawagifexotaxovekugox.pdf In PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/79629446014.pdfIn PDF document text
    • https://dobski.pl/userfiles/file/duforofuminoludi.pdfIn PDF document text
    • https://readandenjoy.ae/userfiles/files/vawoxitawonusosugakata.pdfIn PDF document text
    • http://sammyuriasproperties.com/userfiles/files/59909420162.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/lctrmc27stqljmpnmu7gcp0gg5/87378221097.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5779d7f374---62124355928.pdfIn PDF document text
    • http://zh-huaxun.com/uploadfiles/files/77536751243.pdfIn PDF document text
    • http://eyupsifalibitkiler.com/resimler/files/22196820931.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac4491754e---xiwovuwawabiwusuzoxo.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607a87f0a3477---51488919054.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file///najixodapame.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/mbpa64n5qlj7elcsin6pmo3c27/sebakedidisazikarezaxulaf.pdfIn PDF document text
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/p1bnt6j2s5rkrn1aeeeerma5e7/vejomadorijurugexum.pdfIn PDF document text
    • http://jar-ted.pl/file/nulabanimuf.pdfIn PDF document text
    • http://www.guus.edu.mn/ckfinder/userfiles/files/fogumapozu.pdfIn PDF document text
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/2vbuho1c7gg41idhkjug68utfi/40653271153.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/puwanamolarekuwijimaledo.pdfIn PDF document text
    • https://coil.hk/upload/files/33619706944.pdfIn PDF document text
    • http://4reality.cz/userfiles/files/22387830391.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/0i8dforkkgijj5b1brtepr21g5/vefususeverepegedotif.pdfIn PDF document text
    • http://takeacode.eu/user/d41d8cd98f00b204e9800998ecf8427e/file/giwosaf.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1e0a221721---goxixipegevavu.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160812ede48d0f---65942047434.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=chapter+10+dihybrid+cross+worksheet+answer+key+quizletPDF link annotation
    • http://perfecturology.cafe24.com/upload/editor/imagefile/21377254928.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d8d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f0e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E7 15892 bytes
SHA-256: 2421c6f7b2cc52cb2c73eb69d8323b6ea00a82e777ee611152a3ed2f07f976c7
font_02_sfnt_off000119eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119EB 11552 bytes
SHA-256: 96877acbd4a519c47bae9f1174ed51477bf88524bb06b613b9ba3f167d42dd38