Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8f49eeaef90b5f5…

MALICIOUS

PDF

85.9 KB Created: 2021-09-22 13:46:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 18a241772e6923247289804a045fc323 SHA-1: 6edfae194d3dd91e895a46b356214d382984a0b1 SHA-256: e8f49eeaef90b5f588c79f16fed16fcfbf3d6317a4a0d45f2d8ef816162a79c8
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a ML classifier and ClamAV. It contains numerous external URIs and link farm patterns, suggesting it is designed to redirect users to potentially harmful websites. The presence of compromised CMS upload links further indicates a malicious intent to host and distribute further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://krisoc.ru/uplcv?utm_term=android+video+app+effects PDF link annotation
    • https://serpavenger.com/ckfinder/userfiles/files/gorap.pdfIn PDF document text
    • https://stalbeckers.nl/userfiles/image/file/43343108847.pdfIn PDF document text
    • http://ap116.ru/userfiles/file/boreludipojojimakub.pdfIn PDF document text
    • https://dewalt-naradi.cz/media/upload/editor/file/ridokixupabiluj.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/30c2f1e55c161e5e69ad9a79e6ef2ace/51964599803.pdfIn PDF document text
    • http://hasanmasat.com/ckfinder/userfiles/files/90215208077.pdfIn PDF document text
    • http://sarigol.kr/userData/ebizro_board/file/97228011744.pdfIn PDF document text
    • http://hflchw.com/upload/file/buwupeniw.pdfIn PDF document text
    • http://www.elmundodelapiscina.com/ckfinder/userfiles/files/31083273271.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/5fd91328bcdc858d5118eec6a0f1c337/37267029891.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613046f1c9a93---bemawufemopu.pdfIn PDF document text
    • http://mlead.net/images/e/file/zirukaraj.pdfIn PDF document text
    • https://atavio.ru/files/file/pividor.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140256cbf573---fujaz.pdfIn PDF document text
    • https://svltv.in/userfiles/files/namudoberoku.pdfIn PDF document text
    • http://www.uc-kushiro.net/images/library/File/tenexij.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/101ae586f04398708a1adecd8fec4248/rutej.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/3c8cf4a72e7357bb0e381b94ff948772/wowonap.pdfIn PDF document text
    • https://www.jnvhardoi.org/ckfinder/userfiles/files/33262072608.pdfIn PDF document text
    • http://realfootball.gr/userfiles/file/42504202982.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/5ag6nq6mqc8k0vjjvjjkue8jhe/10162333108.pdfIn PDF document text
    • http://goldenbaycruisesagent.com/userfiles/file/mixesojatodu.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_off0000ec5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC5F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010476.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10476 10616 bytes
SHA-256: d2d30bad9428269cffda6a0315b6ac38b6c7fe8dac823c472cc624f1967f0869
font_02_sfnt_off00011ce7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CE7 17332 bytes
SHA-256: d30da0077b8d021081713da0b626bec807502707f58a5887095fcce9217d4d1a