Malicious PDF — malware analysis report

Static analysis result for SHA-256 39994aece22ba173…

MALICIOUS

PDF

80.3 KB Created: 2021-09-11 18:04:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 19a76c4bc31186ad95075698c4fc8c0f SHA-1: 4f163aecb431795817f1e106fce21f1236df309f SHA-256: 39994aece22ba1732198a56f6c5ddd70fcfa18bf69c752e31244647508a3537c
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple domains, several of which are hosted on compromised CMS upload directories or disposable hosting. ClamAV and an ML classifier flagged this PDF as malicious, indicating a high likelihood of it being used for phishing or distributing further malware. The embedded URLs suggest an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9737

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://maria-galland.ru/files/file/ruwetanijupexutak.pdf In PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/d00e1a20a3df714ffc5276da74aab17a/dajaxo.pdfIn PDF document text
    • http://mispuntossaga.com/campannas/file/ruwuremaxidobu.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131fdf760679---xitunizivojunijusuj.pdfIn PDF document text
    • https://harrisitalia.it/uploads/file/vulavunurokibeboj.pdfIn PDF document text
    • http://kiemdinhcan.com/Images_upload/files/23230167579.pdfIn PDF document text
    • https://alkathirilaw.com/userfiles/files/11701399110.pdfIn PDF document text
    • http://daejonggyoyc.com/userfiles/file/20210906211639.pdfIn PDF document text
    • http://ontis.sk/editor_uploads/system/files/29673416388.pdfIn PDF document text
    • https://nezrenpin.com/calisma2/files/uploads/66880661483.pdfIn PDF document text
    • https://radekslodkiewicz.pl/files/file/debitutojibimuwewuza.pdfIn PDF document text
    • https://seikai.jp/free_images/files/mukokaxuvikedokijo.pdfIn PDF document text
    • https://noursportevents.com/wheelmarine/userfiles/file/jasomanufij.pdfIn PDF document text
    • https://nabijdefossa.nl/upload/files/35961983014.pdfIn PDF document text
    • http://havefuntogether.com/image/upload/File/60041800584.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/375a4490993e0618d894c0c507903ba5/89690519226.pdfIn PDF document text
    • http://bagiez.com/userfiles/file/47438307015.pdfIn PDF document text
    • https://bisnismedsos.com/userfiles/file/8080668730.pdfIn PDF document text
    • http://mea-travel.pl/userfiles/file/tixugaw.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/5aae20cd43a8f79146ba116896b8164c/goropopozew.pdfIn PDF document text
    • http://studiosimonepantaleo.it/userfiles/files/34554205747.pdfIn PDF document text
    • https://oazapiekna.com/zdjecia/fck/file/fopunixudama.pdfIn PDF document text
    • http://gsemilia.it/userfiles/files/zitubowejejilin.pdfIn PDF document text
    • http://mjacz.cz/soubory/files/99724724467.pdfIn PDF document text
    • http://aroma-es.red/yamituki-n/uploads/files/83427757983.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file///18203279206.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=pdf+to+epub+apkPDF 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://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_off0000d758.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD758 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF6F 10312 bytes
SHA-256: fa98fafcb0bf8a9857726b59080aff1f3c238e520b55d164c00656eade36005c
font_02_sfnt_off0001069b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1069B 18504 bytes
SHA-256: 13b65afa4b409133b43797fde52ae3752b07b0ce0a227a31fd21d4e66544d4d3