Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f80e2afdb03a5b2…

MALICIOUS

PDF

69.9 KB Created: 2021-09-18 08:44:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b9e474c1a8c25a8f6c16e65ab1a5756d SHA-1: 82923f1e855d33adda694bb0ab884a3f52b0e4ee SHA-256: 5f80e2afdb03a5b2960a35baa14e40856b142be394cbb4613199eaa02cd00e43
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised websites and potentially disposable hosting domains. The embedded URLs suggest a phishing or credential harvesting campaign, likely delivered via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://coretry.ru/uplcv?utm_term=simple+trapezoidal+rule PDF link annotation
    • http://www.tecs4.com/intranet/ckfinder/userfiles/files/jasiremininog.pdfIn PDF document text
    • http://diamant-x.sk/UserFiles/file/tojazakozojibenulibebu.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/c8cece5e48bbedd472ad8492336a62f4/figerodi.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/hjdrprimvdoac64e5361gegngh/4451864693.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613332ab5ec0b---33883979011.pdfIn PDF document text
    • https://liftsystems.ro/LiftFiles/file/69726106629.pdfIn PDF document text
    • http://archpiudue.com/userfiles/files/15021350196.pdfIn PDF document text
    • http://naturpix.ch/cmsimages/file/25066951381.pdfIn PDF document text
    • http://wordtmann.beckbauer.eu/ckfinder/userfiles/files/65524403747.pdfIn PDF document text
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/ea407717aa8a80d231432dfa57880bb5/jexeg.pdfIn PDF document text
    • http://ntvietnga.com/upload/files/20041178106.pdfIn PDF document text
    • http://abaj.cz/UserFiles/File/91401601865.pdfIn PDF document text
    • http://sellmysayarah.com/userfiles/files/bosibesisikenurafaluvevel.pdfIn PDF document text
    • http://cyuanmei.com/userfiles/file/85655646631.pdfIn PDF document text
    • http://niszczeniewaw.pl/userfiles/file/44138848114.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/2qnqtesjkll0i4hl0rsoaaejmq/43024017543.pdfIn PDF document text
    • http://jhdjt.com/images/upload/File/gofubelo.pdfIn PDF document text
    • http://77owship.netsociality.com/upload/files/pepulobilusuk.pdfIn PDF document text
    • http://1careglobal.com/upload/files/30596003259.pdfIn PDF document text
    • http://vonschickenfremont.com/uploads/files/gapodat.pdfIn PDF document text
    • http://controlsystemco.com/cache/fck_files/file/rixawowuloxev.pdfIn PDF document text
    • http://solis.altrodesign.eu/ckfinder/userfiles/files/47093078935.pdfIn PDF document text
    • http://neoclassicalmansions.com/uplds/file/79524486627.pdfIn PDF document text
    • http://fsgzb.com/upfolder/e/files/20210914102902.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_off0000b1c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c9d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9D8 15948 bytes
SHA-256: cad8aea7e5294be9779bfa5851a4da7d69b948f0c54e152496fc6b3cb6fe0017
font_02_sfnt_off0000f22f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF22F 10516 bytes
SHA-256: a223824ae283c447fdf9059e1a23f677e60df2b3378db04d4737ea29e2e196d4