Malicious PDF — malware analysis report

Static analysis result for SHA-256 8081f18a2688633d…

MALICIOUS

PDF

76.9 KB Created: 2021-09-06 12:05:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 36e6384bd38a8f93adebdd96499de0e4 SHA-1: ca47bffd050bab1d0de6f43b22e7ad8e580b2cde SHA-256: 8081f18a2688633d4fcb03911419737ab99a641922eaaa298d772eda921a0be7
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct textual clues about its purpose beyond the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://laplacedesstores.com/upload/file/68809234624.pdf
    • http://www.aadhar-interior.com/userfiles/file/10888198400.pdf
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/e37c046e2c679b192a9b5f65f3f3b445/73840604152.pdf
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609ef5df06300---tuxekitiwoxewogox.pdf
    • https://egca.fr/userfiles/file/xisaxa.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/93fd4076158703acd000769a20a1dc6e/90908276943.pdf
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d6436536671---gepatulesun.pdf
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/5aa675035b68e856fc3edc21e31bf350/waruxixigiligabozoteve.pdf
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/gjd4k63el0628bih6m0m8porhk/8293391034.pdf
    • http://rolmech-strzelno.pl/Upload/file/xewiketurakuginigegawo.pdf
    • https://nestsearch.in/admin/uploads/file/1985908953.pdf
    • https://tectrongim.com/uploads/files/65141834412.pdf
    • http://koreaseowon.com/ckupload/files/37286353689.pdf
    • http://residencecarlofelice.com/userfiles/files/nozulusodunipozepogarunok.pdf
    • http://hoggard1975.com/clients/a/a4/a43fc1111b7ad4318f8b553feb79a890/File/naselegubesuduz.pdf
    • https://siangyun.com/upfiles/editor/files/58361315584.pdf
    • http://alrabbanoilandgas.com/file/files/92855642189.pdf
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607a02713b010---25768339109.pdf
    • http://archissimo.eu/userfiles/files/62964048443.pdf
    • http://fijiembajak.com/uploads/ck_uploads/files/rigozaxosaveserego.pdf
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/877feda7789715ae74382ffca7be0b4a/kanemuguno.pdf
    • https://songuryazilim.com/calisma2/files/uploads/rezibufapizese.pdf
    • http://mayinluatudong.com/uploads/userfiles/file/37762171225.pdf
    • http://31kouqiang.com/userfiles/file/1624740698.pdf
    • http://geluidsadviesnederland.nl/ckfinder/userfiles/files/nozafeberomaxi.pdf
    • https://misionesmedellin2030.com/wp-content/plugins/super-forms/uploads/php/files/kpvlf8vc7bmq16jhe12k36tc25/4889689378.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=darkest+minds+book+3+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c78f.bin
e3fe7b436510be2fea91661cbf3fdb857fc0dc75137ff7339c5d06a0934f1fb6
pdf-font-stream PDF embedded font (sfnt) at offset 0xC78F 17408 bytes
font_01_sfnt_off0000f4c9.bin
ab4a4569c162245fbf2b3f5ea8b49ba06f4ce2925842005deeacffae135361ee
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4C9 11020 bytes
font_02_sfnt_off00010e35.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E35 16792 bytes