Malicious PDF — malware analysis report

Static analysis result for SHA-256 773c88239e572380…

MALICIOUS

PDF

84.3 KB Created: 2021-07-31 07:09:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 3e5b3258e9c918035dbb4a2489e4eb17 SHA-1: c8377d3bb872065dcd75bc7aabe0834947fc34c8 SHA-256: 773c88239e5723805a2bd448f8a8afeb105dbb976f1b7be118fa745163ad88f4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links pointing to various domains, many of which are hosted on disposable infrastructure or compromised CMS uploads, suggesting a link farm designed to distribute malware. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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 http://esthebel.de/userfiles/file/84420301897.pdf In PDF document text
    • http://haus-st-otmar.ch/userfiles/files/datafositesulu.pdfIn PDF document text
    • https://scriptdd.com/_file/file/78656560206.pdfIn PDF document text
    • http://dajuicebarus.com/uploads/files/nivoz.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b7e6f897fd2---sefalivonevulige.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160795a40da483---xovawixoxux.pdfIn PDF document text
    • http://rajskiewakacje.pl/userfiles/file/31807685483.pdfIn PDF document text
    • http://bluiettgriffinwilliams.org/clients/2/2a/2accc941c041fffeac9751862bb8fe41/File/tegasesu.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607ecf7f4892b---fapigikowejanosufopisug.pdfIn PDF document text
    • http://juhaszautovill.hu/userfiles/file/59755459423.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file///14332979653.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/161004c8f8b535---dakuzifabipalada.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/2ebup3gkk94qaj4e3iqo5k2uo4/33351792560.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a05d8b4ca59---taxizurozejujud.pdfIn PDF document text
    • http://zatacorp.com/upload/files/42341328051.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/b9383e90f2872d6a7a868193eeb16cdc/koxuvepadegiguse.pdfIn PDF document text
    • http://bollywoodsalonskokie.com/admin/images/file/dasuligivogowelif.pdfIn PDF document text
    • http://wijnhuis-vaessen.nl/site/data/ws/files/kobofesoliwapibemif.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/i32jejs8f1vrmccba2uvf81dv6/12498488032.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/suxuwijogoj.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160db8af81bb0f---gowurezevumezotukimetuvob.pdfIn PDF document text
    • https://pensiuneavlasin.ro/wp-content/plugins/super-forms/uploads/php/files/i318bpfhi19c12pehodg6jav2k/55813278433.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/571a288fe345249aff4dc165cea2efa8/wamewubozup.pdfIn PDF document text
    • http://mp-journal.com/media/file/47104818612.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7c5608aea3---68600879328.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f587b9a33ce---linusudaxobodot.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=farming+simulator+17+key+generatorPDF 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_off0000e529.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE529 10836 bytes
SHA-256: 23a17f92a5034f940a209fb9116c700fefde9c03581537032d27ed6ad51efdda
font_01_sfnt_off0000fe47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE47 17088 bytes
SHA-256: ee38775203552b070744d4e7a64649655bf8ee5abfc0033ae4543023a922ce61
font_02_sfnt_off00012ace.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12ACE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1