Malicious PDF — malware analysis report

Static analysis result for SHA-256 71f4cf7eaf63dfc1…

MALICIOUS

PDF

81.8 KB Created: 2021-09-13 09:01:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 27d7daf3e8224969b4baab5454838b98 SHA-1: dab6f5fde52d822d1a35444e4b0e1e4cc000f71f SHA-256: 71f4cf7eaf63dfc1848bb2d76dc6e60e3b85fc5be79fdafb27b8e776d4d39314
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to various domains, many of which are flagged as link farms or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The authoring application 'wkhtmltopdf' is also noted as a potential indicator.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://allytemp.ru/uplcv?utm_term=robux+redeem+site PDF link annotation
    • http://elskenecologie.nl/files/jawugebed.pdfIn PDF document text
    • http://4x4autok.hu/userfiles/files/xejad.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021090410514837.pdfIn PDF document text
    • http://wowbond.com/upload/Fckeditor/file/tevamosexokabajupe.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613946b9f09d8---xepunezedufukobevabavutu.pdfIn PDF document text
    • http://alacarte-grafik.de/userfiles/file/milejurov.pdfIn PDF document text
    • https://onlinendttraining.net/files/fezizejirimivevuboxa.pdfIn PDF document text
    • http://futurepoolandspa.com/ckfinder/userfiles/files/42679362751.pdfIn PDF document text
    • http://ndc-group.ru/uploads/files/fijotisemalerowupe.pdfIn PDF document text
    • https://fontan-montag.ru/img/upload/20919278140.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613864436bb08---81872656937.pdfIn PDF document text
    • https://smartcrm.cloud/upload/files/40902307769.pdfIn PDF document text
    • https://aldaserwis.pl/ckfinder/userfiles/files/lifejoseta.pdfIn PDF document text
    • https://tl-systems.hu/files/files/51016520312.pdfIn PDF document text
    • http://portalcom-b2b.es/img/user//file/_0123321001630627466.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fa90f7e889---45628272175.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161384ef6f0e91---donesewevumijuxerik.pdfIn PDF document text
    • http://thebookmarkcafe.com/uploads/files/levalikesutiwenozu.pdfIn PDF document text
    • http://www.accl-calibration.com/login/ckfinder/userfiles/files/25331277174.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/tadofemewukamebirosunaka.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f509f5a097---lekanul.pdfIn PDF document text
    • https://fa-vietnam.com/webroot/img/files/zixopuzuvifutuvug.pdfIn PDF document text
    • http://yh-nutri.com/filespath/files/20210905075151.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_off0000cedd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEDD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e6ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6EF 15264 bytes
SHA-256: 2e7e36d319a6fc7df657c5e7aa5befdf1c531e0c76dd9c185fa0d7e086d96328
font_02_sfnt_off00010de7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DE7 16928 bytes
SHA-256: d5b30b7550dfafb80c399c54411485f8761850fd4e643de637ea00d0050c8eaa