Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f87f8fc13e69a7c…

MALICIOUS

PDF

105.4 KB Created: 2021-06-26 11:18:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: e32137ef15b1894d60cc70ba2efd5b6b SHA-1: 7f9ca5979b504d35cb309a66968fe6a226bd3f5f SHA-256: 3f87f8fc13e69a7cff9c5078b48895336c14367951e054961f57fd7b9512b737
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised websites, identified by heuristics such as 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV also flagged this file as malicious. The primary function appears to be directing users to potentially harmful content hosted on these compromised domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9790

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://ruegen-ferienhaus-schneider.de/userfiles/file/gazobatolisadisefulajidil.pdf In PDF document text
    • https://bibliotheque-des-arts.com/ckfinder/userfiles/files/rotizilakaxitineborab.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/8ba73e7cd6687af25b253ef40e5da037/jomude.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/96920670619.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac053ee813c---gokobusuxas.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/mazubuzifeveweziguwuzex.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160707e22f23f2---98086858115.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/8ac64b87bbe3ca2c9a692f2a95b794a6/71075156891.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/igtr3ms4jv180eaofaso3me94a/27502429065.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/abf1dc64cab7fe2398479f4d41b2f314/65281213675.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/3b004437a0c467eac3bf4cde766be135/wotedugavumejiporoladipom.pdfIn PDF document text
    • http://singer-island-condos.com/userfiles/files/golinomufibiziv.pdfIn PDF document text
    • https://betentour.com/sites/default/files/file/bivijekaboduvibonet.pdfIn PDF document text
    • https://artbynela.com/uploads/file/50077095040.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac03b83af7b---jovakolisusozezejefujomaw.pdfIn PDF document text
    • http://resortcrimea.com/ckfinder/userfiles/files/85541715669.pdfIn PDF document text
    • https://purmoradiatoriai.lt/images/files/zunisebonejekiguxikoso.pdfIn PDF document text
    • https://dixietemporarystorage.com/wp-content/plugins/super-forms/uploads/php/files/d24dbdc385aaee54435959457f59e823/83042969535.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e66c20c4c4---nitepevufarisexanu.pdfIn PDF document text
    • http://riggi.ru/userfiles/file/26013390486.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/d50275a6a43fd005887ae3a385d98bb4/vigalilazemokojatiguduf.pdfIn PDF document text
    • http://short-story.ru/upload/file/webel.pdfIn PDF document text
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1609e41f21777f---panomep.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606c849ba157c---vagodikixe.pdfIn PDF document text
    • http://benly-carson.com/product/files/rapuvotafekizegusinevef.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a99c7dc3287---mafowalawi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=do+you+truly+love+me+quotesPDF 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_off00013c76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C76 17312 bytes
SHA-256: a8740f61012449d33daffd6107c3df2f80fbee27a925722e9df72f58f85ab5d1
font_01_sfnt_off000168e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x168E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000180ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x180FF 10340 bytes
SHA-256: 54d461ff80671ad59571235de064a0889b808ef7b87bc4d1f637673b6e2d6932