Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b6a88465281ebd…

MALICIOUS

PDF

91.0 KB Created: 2021-08-07 16:09:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 761ca76e2d0f526a2ecffcec7ea7189b SHA-1: 84519c5391f9bc1fcbe5cdcdedd280ade7082f0b SHA-256: 77b6a88465281ebd12e15d73646a77c27973d37ea70bc889580abe8ebd94eca1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. Multiple URLs point to compromised CMS uploads and disposable hosting, suggesting an attempt to obscure the final destination. The PDF structure and embedded URLs are consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/c8cb1255affad5e78cf9b2c97dce3577/16700991446.pdf In PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160828172686be---19618249690.pdfIn PDF document text
    • https://ssmahavidyalaya.org/lion/uploadedfiles/fck/files/file/16854690109.pdfIn PDF document text
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/160f01f2ed5e61---80770599911.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/160883b036ed86---ximoxumujasimaxux.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/r2ebn4ie61ggfnaa62i6qkfc6n/33754502619.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/3a37f71d0645b605c78d9223afae74e2/38482057432.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/7ddcca2ffa728d382f30a04b03fab3bc/80511221942.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d472356303---supukonefemasewo.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16106686209760---29904526840.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160a88c7634039---xamenojegotuwivovijuwux.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/161058eb53ffbc---loziwa.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/86bf57f39e6b715c3ea7779eb184b7d9/39475850907.pdfIn PDF document text
    • https://bloomland.com/sites/bloomland.com/files/95496434091.pdfIn PDF document text
    • http://lsbwg.com/ckfinder/userfiles/files/20210719/1857502728.pdfIn PDF document text
    • http://haphadoor.com/upload/files/7979633458.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c103caa45b9---39231213261.pdfIn PDF document text
    • https://zionapostolicministries.org/uploads/files/lowufakeximutiwikixevonu.pdfIn PDF document text
    • http://74ahs.com/clients/2/2a/2a132ee8da0778863662fd4b1fa251ed/File/91933021421.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9b53b45e09---tujunuti.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160984eb80e3fe---nutotunowutosekozebix.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160c887c65e0b8---59015756244.pdfIn PDF document text
    • https://legyenegyjonapod.hu/userfiles/files/wetafase.pdfIn PDF document text
    • http://atsrealtyvietnam.com/upload/files/65362772352.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=star+trek+movie+2009+free+online+streamingPDF 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_off0000fe0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE0D 16876 bytes
SHA-256: a4beba28d49c985eb41c34cd159d1a7ad0f70168199e039609157034ad60c5b0
font_01_sfnt_off0001299f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1299F 11200 bytes
SHA-256: 83ca072905fc984f3b2079d5692d30ba2a7d6fbacba996d4cb26a1686a2f77fa
font_02_sfnt_off000143ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x143ED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1