Malicious PDF — malware analysis report

Static analysis result for SHA-256 61ac79e5f78b7432…

MALICIOUS

PDF

86.7 KB Created: 2021-07-24 23:41:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 00ec3273894a10e6600d9e85867fdbe6 SHA-1: 24cac66b87891f8b0924e34f9e53c3c461c2661a SHA-256: 61ac79e5f78b74327ce536a879c62af1c44cb7ea08034dab0d5987a7e401fa9e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains a large number of external links, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to download further malware or engage in phishing. The document body is unreadable, but the heuristic firings clearly point to a link farm designed to exploit SEO or direct users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606da03336e06---1118534556.pdf In PDF document text
    • https://bravo-hk.com/userfiles/file/wixexovegolaza.pdfIn PDF document text
    • http://allseasonsart.com/uploads/fck_uploads/file/77432875990.pdfIn PDF document text
    • https://dennismaloney.ca/upload/editor/file/sivuwapi.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210723115359_m425rj.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/ki0u539gc7mg2okv9mr34f6mv7/dorufukatinam.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca0dde479f---zalufokago.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/f19ee862eaa6b3c9dc80ef2a19f2bc06/jufisoratijaxujikelo.pdfIn PDF document text
    • http://sentralperdana.com/file/23232536413.pdfIn PDF document text
    • https://traonguoc.vn/wp-content/plugins/super-forms/uploads/php/files/o7pn1haopa6a9chnfo0k4dflj4/19169938254.pdfIn PDF document text
    • https://imagebuzz.net/ckfinder/userfiles/files/21431551388.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/abf70ea06c9f2c26d6203b26ca2513cb/panigumuzonogugetaf.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/pajevadobojununutopalu.pdfIn PDF document text
    • http://sl-light.ru/design/img/upload/file/mominenovowagejezisij.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/ff6n6n0iurterfmrkiako5rrh3/divexon.pdfIn PDF document text
    • http://asja-doll.ru/userfiles/file/wefurabezamij.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/f55c57422d59e6a27128bae480780259/miravijuzujorodadog.pdfIn PDF document text
    • http://retrievers.su/ckfinder/userfiles/files/musitugedozad.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160f6e84166d4c---kodibojan.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160f28c165d60b---47100676927.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/be61bd9578e20c799fbade05e03c5e07/13914400064.pdfIn PDF document text
    • http://faradbox.pl/files/file/raxudetu.pdfIn PDF document text
    • https://balajihighfields.in/userfiles/file/76617127195.pdfIn PDF document text
    • http://vtdsbinhthuan.vn/public/uploads/userfiles/file/vorudawaxosid.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2ca456dcb---vuvibowakunowesobobobab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=driverpack+solution+offline+2016+free+download+full+versionPDF 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_off0000ed45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED45 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010557.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10557 16792 bytes
SHA-256: a1b5c90226429c6507b1ebb4d770e6a8d11a448437d029f8fc7b61a8d94db956
font_02_sfnt_off00013150.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13150 11420 bytes
SHA-256: dd55c5a8125f2b67b94ccd604140779842f806532a15f4a634ee52a341c2f997