Malicious PDF — malware analysis report

Static analysis result for SHA-256 637e5dd7ae9a9c5f…

MALICIOUS

PDF

88.3 KB Created: 2021-08-12 17:21:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3f00eff38c26da8af59acc06b6788dd2 SHA-1: 4ae0c88927e5331bff4866b2c2ba3495c154e6bf SHA-256: 637e5dd7ae9a9c5f3ceb55bcde64542351d92d8c20b354cc7d297b0ebb151dae
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised CMS upload directories, indicating a link farm strategy likely for SEO poisoning or phishing. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery, often involving embedded JavaScript for obfuscation or redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd359734cbc---23052157424.pdf In PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/b486970cbf37abd08ce7824cab4d4dc7/fegojinizokejopita.pdfIn PDF document text
    • http://www.firengo.com/userfiles/files/kagapul.pdfIn PDF document text
    • https://www.erenang.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083881b446ba---fogetumusirosavul.pdfIn PDF document text
    • http://xn--h1aaebbkfib4a.xn--p1ai/sadm_files/3038654240.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608ae1036f9d3---nugibojozu.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/47218032466.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/cb055fa1326d3fe74dd6002c7a7c8d2f/nezilen.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/ef10eadc4897af67b26b9d1b7fe08f06/77858905839.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1e8619b4fa---10489561272.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/16090eb5d6761c---25326228034.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1607777fd28a47---suzapujofamema.pdfIn PDF document text
    • http://meta-min.com/files/kinolezemipig.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/08bde594cd95e5fb8c2dfa9a8acca193/babiv.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/s7prphq0cmikm58q7pf65p8je7/sanuvojidunox.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16086caaf08d8c---seporedubinavebifupewu.pdfIn PDF document text
    • https://alsterparkett.de/wp-content/plugins/super-forms/uploads/php/files/a8l0emtl6bo9i24rigq724eqqp/bapixebitexiposekix.pdfIn PDF document text
    • http://globalnetworks.de/www.galabau-poscher.de/main/preview/ckfinder/userfiles/files/josoze.pdfIn PDF document text
    • http://puppies-4u.com/clients/e/e7/e7f09595da74c05d2059c741134300d2/File/bevufetamaxu.pdfIn PDF document text
    • https://doktor-ara.com/userfiles/files/jefemulefo.pdfIn PDF document text
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/vumurusiliwivuza.pdfIn PDF document text
    • http://anaminfo.com/attachfile/file/70479456174.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b4fc1fcff2e---84133015594.pdfIn PDF document text
    • http://sarlampa.ru/upload_picture/39397617031.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=what+is+the+enthalpy+of+neutralizationPDF 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_off0000f1d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1D9 18408 bytes
SHA-256: 797b697df7eb7427950d87d4ea2a5bbc57997b221b20804dfd0d939bbbfc5362
font_01_sfnt_off000122c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122C7 10724 bytes
SHA-256: 4aa4269dd689b105612a54e5f76131a74469fb2c41b80af7bc606afee4f6175f
font_02_sfnt_off00013b6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1