Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5671cbb4982e05f…

MALICIOUS

PDF

87.0 KB Created: 2021-07-03 22:23:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 27013bd146eb821a99565c4ea726ec16 SHA-1: ca878b286053ee40e9bdef99e9273661edc9ecdd SHA-256: c5671cbb4982e05f1a31c10c93bfa21a3718349231237b72d6c7bd1f2a00a79d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The file's structure as a link farm on disposable or compromised hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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 https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afe56e95ef6---39609910888.pdf In PDF document text
    • https://samarpanbharat.org/trila/userfiles/file/51296459512.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1a5a0b2bf---29538699446.pdfIn PDF document text
    • http://elijahlaurabishopblack.com/clients/b/be/bed082b287f5bb70db4763ab929fc18a/File/mubudaxizofelasurupel.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160737686bdeab---68790161571.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/39edb630ee815c9a64bfd0b3ed1d8988/naritetisakavuwonofomav.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/rte5em6tlj9o0e28v27omp6pj9/baluruno.pdfIn PDF document text
    • https://caribemed.com/userfiles/file/gukeziluxozebuwamagoza.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/7df438a3bc23559ffaaf2ac47d108ec0/74349116503.pdfIn PDF document text
    • http://tourhong.com/FileData/ckfinder/files/20210628_28F71E10EFE00A7A.pdfIn PDF document text
    • http://xn--54-dlcdkamdj4btild5b.xn--p1ai/ckfinder/userfiles/files/viloved.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d74422f2445---24431673125.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fbdfea13af---38071181759.pdfIn PDF document text
    • http://hnc2.com/userfiles/file/9118687995.pdfIn PDF document text
    • http://marcobernini.it/userfiles/files/popoko.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/69548d0ad2cd288299af880def34f847/gojapexufil.pdfIn PDF document text
    • http://medicamarsala.it/userfiles/files/mesibowigumotifobotonut.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c488925729f---vemitemomodebazazix.pdfIn PDF document text
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/8k0j7m01sudvrp0q2qq7g6t6g3/xanusen.pdfIn PDF document text
    • http://vitanova-cattery.com/upload/file/laliriravev.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/31066337065.pdfIn PDF document text
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/cb9206f61ac999c9ecc90688cd868d28/wawewixamilulom.pdfIn PDF document text
    • http://alemotta.com/resources/original/file/62985075745.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b486499d433---sujidedenu.pdfIn PDF document text
    • http://wittlich-luexem.de/userfiles/file/xogoporesuposozupifemug.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=the+kitchen+table+series+1990PDF 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_off0000ef45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF45 18184 bytes
SHA-256: 4b81998d4a2bf405a25e1bce48e1360b32b1abbb0daa78dd30d760456f2fda26
font_01_sfnt_off00011e33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E33 10744 bytes
SHA-256: cfcd9ad93a5f1dfa0b16706ddb1d7c3ba01c1ad6d8fa944136f79b0b13f3c396
font_02_sfnt_off000136ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1