Malicious PDF — malware analysis report

Static analysis result for SHA-256 855f4058c621bd70…

MALICIOUS

PDF

275.2 KB Created: 2021-06-29 11:47:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b5b63fae6137878430ca8d2b78775e3f SHA-1: 3e99dd3d750179baf10b2ad82c07914bd984325b SHA-256: 855f4058c621bd70d2713fe1c99aa77bba5d33592ba00036401f35c17ea310d5
206 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating a phishing lure, specifically impersonating Microsoft and directing users to a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were extracted, the presence of numerous links, including one hosted on a compromised CMS upload, points towards a credential harvesting or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9692

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • Brand-impersonation credential phishing lure high SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: call-to-action link host does not match the impersonated brand: https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+answer+questions+in+paragraph+form.
  • 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.
  • 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://morethancars.nl/uploads/edytor/file/15421009765.pdf In PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097d676dc57c---47070022236.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/32d8e3611da783ce7dd677e01657e338/19400186649.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/dr19gia9t331t5v72gp8k71in2/49974238848.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160743356eb829---zemekufokuzaz.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608749401094f---vosetetagujujefu.pdfIn PDF document text
    • http://myjobcareer.net/userfiles/file/2021060902363473499.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea3067ec63---55466643893.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/taxefogafekiwepunesefup.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/paj9m6c10o00593sk4uk0setr0/70237000903.pdfIn PDF document text
    • http://amdind.com/userfiles/file/58255451991.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/bc333fc4b28cac2ff249d1110a3b0b6a/73207465704.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607a1fe36b501---naribofox.pdfIn PDF document text
    • http://namlongprojects.com/images/uploads/files/goreram.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/1a75e5b96628331cac7bee9efad2c12e/tumifina.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3fd75d870---mepez.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160da4998863ed---73527658654.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608728175d095---65021193636.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608da6f037bbc---kasuzamiluxixikolizodot.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/8e2970b5fddaf5438e53ac05116cd9e4/29966860531.pdfIn PDF document text
    • http://vistobrasil.net/uploads/file/jitirarobakino.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a403d8a115f---boxatirimupose.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160bb028d5ded2---68318999046.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/8a8f42a49e94652e9f85f16559c5bba6/85454859568.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607ef366ef3db---moremabevonagalidotanu.pdfIn PDF document text
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/nbc8f8cgl3i7jv8fmnd5p95m8s/3207084204.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+answer+questions+in+paragraph+formPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0003be8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3BE8D 11080 bytes
SHA-256: 1833337ef2f3add649f5daf50f9d31d3fa22bfaac49d7988049b07e60b1a5090
font_01_sfnt_off0003d7e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3D7E4 16536 bytes
SHA-256: c7cbd525fe5ac0925699b9a682fc3cb735c1352e100803730c02723aaeb22e12
font_02_sfnt_off0003eeac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3EEAC 21044 bytes
SHA-256: 16c342560ec2a1a82bb287d416ac60cc3f13440c667e20d62a0e7b7b19dd7b86
font_03_sfnt_off000425ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x425AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1