Malicious PDF — malware analysis report

Static analysis result for SHA-256 5be51d9e71feba6b…

MALICIOUS

PDF

79.8 KB Created: 2021-09-02 08:37:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 16bf0951a61055c81e415c362f4e3df5 SHA-1: 29f4a48a06d186d4a01807091a13e5c5a945503d SHA-256: 5be51d9e71feba6b9bec6cebaf8b5370f7053ff77255384bbe34ec3270932510
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting. Heuristics indicate this is a link farm designed to obscure the true destination, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 http://wrtour.com/FileData/ckfinder/files/20210820_E979F53FD2D5FB34.pdf In PDF document text
    • http://clair-environnement.eu/catalogue_dynamique/file/65362643040.pdfIn PDF document text
    • http://ledspectrumthai.com/ckfinder/userfiles/files/70661197148.pdfIn PDF document text
    • http://misr-consult.com/userfiles/file/12933761675.pdfIn PDF document text
    • https://nabijdefossa.nl/upload/files/veforu.pdfIn PDF document text
    • https://upaspor.com/resimler/files/7485977818.pdfIn PDF document text
    • http://studioego.cz/userfiles/file/17294746653.pdfIn PDF document text
    • http://webatnet.de/ckfinder/userfiles/files/vafazijitarawu.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/2082c3a7c107fe780f9c8a00ba4f716d/3307800204.pdfIn PDF document text
    • https://annjulieskarpmo.com/userfiles/file/kegib.pdfIn PDF document text
    • http://dichvutot99.com/webroot/img/files/savijajejovitid.pdfIn PDF document text
    • http://i-daa-wl.de/userfiles/sezimebodaluzanumibebeb.pdfIn PDF document text
    • http://xn--sanitrprofi-p8a.ch/fckeditor/editor/images/file/86977432471.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca058196640---vadeburojodadewono.pdfIn PDF document text
    • http://holidayservicemarsala.it/userfiles/files/50652795051.pdfIn PDF document text
    • http://sieuthivatlieuhoanthien.com/upload/files/puwumizikagoki.pdfIn PDF document text
    • http://congtyvima.com/images/Download/91185134267.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/161032d82cb9a5---82671736244.pdfIn PDF document text
    • http://www.moyekolodin.com/files/48840930070.pdfIn PDF document text
    • http://www.kymenhome-etsinta.net/tiedostot/files/23865962094.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb7c7854e46---nikubexipagufol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=national+building+code+2016+part+4PDF 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_off0000d103.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD103 11280 bytes
SHA-256: 5e4fb41ad892213f4e7ac505b0636c5caa6547dc5e0fa0686878178667f16d7e
font_01_sfnt_off0000eb42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB42 18196 bytes
SHA-256: 7b2bc0a5cf05ea074a4a924313d435dec4970b709d6cc2d6c95ef24d6ac0da34
font_02_sfnt_off0001197d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1197D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1