Malicious PDF — malware analysis report

Static analysis result for SHA-256 4639a328ffbfdb31…

MALICIOUS

PDF

71.5 KB Created: 2021-09-30 19:13:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 413c936e22dce467e556f0e5cb449f35 SHA-1: d661052a3668ae5d55bf27aabb796055dea76296 SHA-256: 4639a328ffbfdb31879861faa7b9548b72c8747f58acf814594fcc283fb9e469
96 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress sites and other potentially untrusted hosting. The ML classifier strongly indicates maliciousness. The primary function appears to be directing users to external, potentially malicious, websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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://foundryindia.org/userfiles/file/63666312008.pdf In PDF document text
    • http://old.smartplus.pl/ckfinder/userfiles/files/vawawuwinobidijopaf.pdfIn PDF document text
    • http://pmrs.ps/userfiles/file/gosarovomaruxurem.pdfIn PDF document text
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/3974bbea091705844db2238e52291ac7/15794399684.pdfIn PDF document text
    • http://zuszdounky.cz/files/xobuluwugokogigisape.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/m2mjh0tu4p1b8uicf4pie8u10q/71319375608.pdfIn PDF document text
    • http://www.de.ruben.pl/ckfinder/userfiles/files/gozetapog.pdfIn PDF document text
    • http://ltmetal.com/userfiles/files/tuzovedatajevo.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16153fbbcec887---21594102672.pdfIn PDF document text
    • http://digivideos.net/ckfinder/userfiles/files/derofetewavan.pdfIn PDF document text
    • http://www.anglometais.com.br/adm/Editor/ckfinder/userfiles/files/zawumovufevomaxazelapeju.pdfIn PDF document text
    • https://essuances.com/ckfinder/userfiles/files/76511066340.pdfIn PDF document text
    • https://eco-translation.ca/upload/editor/file/vuwologubaxidelikifudo.pdfIn PDF document text
    • http://gapp.fr/medias/files/53011350268.pdfIn PDF document text
    • http://gr-chem.com/upload/files/zewiraburabolarabare.pdfIn PDF document text
    • http://pluimveebeurs.com/userfiles/file/52864459484.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/825f3fd5fa2cab561ea68bf1fe0131ac/filuvuzunosabe.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/4cae1d34e5ef4f3fb589bbd79c8f5fd8/99229689155.pdfIn PDF document text
    • http://www.tahi.hu/ckfinder/userfiles/files/bozivamibimizod.pdfIn PDF document text
    • http://osoboebludo.com/ckfinder/userfiles/files/3854439243.pdfIn PDF document text
    • http://ncdesign.it/userfiles/files/86665001862.pdfIn PDF document text
    • https://biharlokmanch.org/userfiles/file/vuguzalak.pdfIn PDF document text
    • https://ibexquimica.com.br/ckfinder/userfiles/files/69262484405.pdfIn PDF document text
    • https://officialbacknumber.org/editor_up/bofutipudojexaku.pdfIn PDF document text
    • http://dribblebar.pl/userfiles/file/17636790326.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=android+tv+app+iphonePDF 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_off0000b5ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5AD 10324 bytes
SHA-256: 3490d46251beeb82fb7f3570ef529d6b255e4bb43171eb5a5a98877ee2d3f4ae
font_01_sfnt_off0000ccdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCDD 17016 bytes
SHA-256: 7b6f49907e8127164305cbf52b84d99445cec32f782615cf5caf2e74388a76f0
font_02_sfnt_off0000f83a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF83A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1