Malicious PDF — malware analysis report

Static analysis result for SHA-256 989ad3715bfdafad…

MALICIOUS

PDF

86.5 KB Created: 2021-09-05 16:47:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b7566f8d3d80e4d71782b847cd39cf1a SHA-1: 074013d2c7be3f3b64a4223220e543ca584f6108 SHA-256: 989ad3715bfdafad210d09ff469373e5bb989ce81e42b62c5c76c43264377347
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm or phishing lure. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this. While no scripts were explicitly extracted, the PDF structure itself likely facilitates the redirection to these malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a99d3b86fb9---23370564402.pdf In PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ba7ad0313b---65072866286.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/ca29a7dfff4aa91037c3ae4ae518eeb7/70038584961.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b429addd8da---21936569884.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609448df5aa85---tapeviv.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee0e1215e3---bidorivifelo.pdfIn PDF document text
    • http://win-sonic.com/kida2018/ck_imgs/files/29489178177.pdfIn PDF document text
    • https://muahohangnhat.com/app/webroot/uploads/files/85048609325.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085d50406576---90350978786.pdfIn PDF document text
    • http://bagumul.com/file_upload/spaw_upload/file/20210812185755.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/d10826fb1f9d04051861f173ed7b6beb/dorupeladopuvazab.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160867ed2c4b98---vebizivamozidemovolezaris.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086daacb8ba2---bivokakepinegasokum.pdfIn PDF document text
    • http://peaceinsrilanka.lk/userfiles/file/kodif.pdfIn PDF document text
    • http://jtylek.pl/Upload/file/zemenorovuzajirimumikora.pdfIn PDF document text
    • https://syntellect.ru/Repository/file/nitajofu.pdfIn PDF document text
    • http://sapaelitehotel.com/webroot/img/files/35483553989.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/lugokanogalivubejo.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/16120a46281b55---20172424930.pdfIn PDF document text
    • http://bezagsecurity.cz/userfiles/fuwibarawufenazu.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/jc9d205i71qmd9ocgf3tp2vdu6/vawiwurixerosigajesovaj.pdfIn PDF document text
    • http://citra.cl/userfiles/file/werujeruvujewurijepizamos.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/joreza.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/file/kekaxapadopubiguxi.pdfIn PDF document text
    • http://savitapiti.org/ckfinder/userfiles/files/sosenirok.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=california+mathematics+grade+6+pdfPDF link annotation
    • 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_off0000ee5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE5F 11268 bytes
SHA-256: 99ce6e539040b853d7555418590512b0374d697e72d6bcac6cb2ae09673cfe5f
font_01_sfnt_off00010864.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10864 16820 bytes
SHA-256: a98cb3e4553a9a3e9a1fe37c9abdebb667de7bd033a22c10b111083dc3fc5ae1
font_02_sfnt_off000133b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1