Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5b1f45fb78c5167…

MALICIOUS

PDF

81.9 KB Created: 2021-09-22 09:29:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c64c83f74eead0e155fd0f4efeaca7c8 SHA-1: 7e04f353a5a59859512d5efd65ea53dd46a268fc SHA-256: b5b1f45fb78c51670ff2559c3e0ac5b97848df4dd8c241520595b06f2339937d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of techniques used to host malicious content or redirect to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://laborke.ru/uplcv?utm_term=how+to+backup+and+restore+android PDF link annotation
    • http://superazs.ru/images/news/file/bosijadipologilezusujapag.pdfIn PDF document text
    • http://pokorny-podlahy.cz/UserFiles/File/vekupijivapevonumo.pdfIn PDF document text
    • https://spa-salon.ru/ckfinder/userfiles/files/wugitatojuro.pdfIn PDF document text
    • http://eiffelflowersquesnel.com/userfiles/file/43419283544.pdfIn PDF document text
    • http://historico.uts.edu.co/portal/app/ckfinder/userfiles/files/43149005434.pdfIn PDF document text
    • https://www.netcorp.hu/data/editorfile/67524615506.pdfIn PDF document text
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/87696230388.pdfIn PDF document text
    • https://matrixx.lu/images/dewaxajofisabukaxafemixup.pdfIn PDF document text
    • http://godsownproperties.com/userfiles/file/27613424505.pdfIn PDF document text
    • http://ehoron21.mn/uploads/files/kudulapuluw.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147f36782b02---betekafujasuke.pdfIn PDF document text
    • http://purofirstli.com/userfiles/files/65318542288.pdfIn PDF document text
    • http://simpelms.nl/userfiles/files/wevozirepanawulofadunasu.pdfIn PDF document text
    • http://www.beverburcht.nl/upload/files/zewifebijularojilorogixiz.pdfIn PDF document text
    • http://st-johnson.com/Uploadfiles/files/pevunitek.pdfIn PDF document text
    • https://theshamrockpublecco.it/file/27251764215.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/79698674528.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/6625957e5409ff743e4a51c8a9b6c77c/68471574152.pdfIn PDF document text
    • http://instit.ac/ckfinder/userfiles/files/70629207103.pdfIn PDF document text
    • https://mastirz.com/userfiles/files/vaxofezejafojobelosipe.pdfIn PDF document text
    • https://www.autopsrus.com/ckfinder/userfiles/files/gedoli.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/e1d68d5253d8dcadac11e270dfaef347/soxevem.pdfIn PDF document text
    • http://ortopediaszombathely.hu/editor_up/29486320720.pdfIn PDF document text
    • 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_off0000dac2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAC2 18068 bytes
SHA-256: 4cd74492a08e4f149f4c301f35fa2d28c9ea71dc3e89708be141d694ab4c9541
font_01_sfnt_off000108d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000120ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120EC 10872 bytes
SHA-256: 6bcae3ed4c025597f2a21fa3ad470118694be961497ae46a1ed32ff68501abe9