Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b97d0c93d5ab9c1…

MALICIOUS

PDF

88.9 KB Created: 2021-07-09 18:06:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: a8de1e93e841c7664ce9cfba0a792a14 SHA-1: 2336137441a57a91c66e389929fb45603dc6b64d SHA-256: 5b97d0c93d5ab9c11f1ced562b9235d5e938895a37b49a486cc447dd1a0b5faf
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains embedded JavaScript and a significant number of external links, many pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery through these links. The embedded JavaScript may be used to further obfuscate the malicious redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=krathwohl%27s+taxonomy+of+objectives+in+the+affective+domain PDF link annotation
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/pvaocglm2rbvanlab6aclml8af/nelitoxofudaw.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/10adfa93904f6c716b70827e2c3fb02e/5378946801.pdfIn PDF document text
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160be364fbc9d3---dusebimubemupedimupinavo.pdfIn PDF document text
    • https://tosto.cl/ckfinder/userfiles/files/jofolujasutawikokiba.pdfIn PDF document text
    • http://diamondsnspurs.com/clients/12200/File/zixolubawifaxiba.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608687fd0908a---64469237874.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/8fb21e9f1c47e934a71ff84b245e2a36/firuputupexuxaxiteju.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/0666d8eb40388e8216e4b17662aac289/worebig.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/e25a704f16ddbf86a1edb391a3922c00/gorutugimo.pdfIn PDF document text
    • https://eatorhours.org/e-bussiness/fckimages/file/fanupijogijuf.pdfIn PDF document text
    • http://happyhanool.com/ckupload/files/30772381389.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/619892e8c5765e71303eec3a250e4625/xobokekipanizaz.pdfIn PDF document text
    • https://jodhpurtravels.com/nbloom/fckuploads/file/fefuvepavirumedidawego.pdfIn PDF document text
    • https://cecprint.com/images/file/95179997224.pdfIn PDF document text
    • https://corumosmanlimakina.com/js/ckfinder/userfiles/files/84962012810.pdfIn PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/dusuru.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16079e12f0e554---67817219467.pdfIn PDF document text
    • http://metaglas.kr/userData/board/file/dozoje.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/bcb1121ee1ff3f08529b685c51d497bc/60415848546.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/160dab4d4b3cbd---fekanabojixof.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa25a650933---mizox.pdfIn PDF document text
    • http://deasreunion.com/clients/860224/File/20230492441.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_off0000f534.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF534 11404 bytes
SHA-256: cc52392fc4105a0926e96727d6599055c64e6e3735818a7eaaa540bb5531aad1
font_01_sfnt_off00011011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11011 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012823.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12823 17376 bytes
SHA-256: b176db79270b08b5add0c9b37818bb12243271a415c35343d24ad9feb0e0b5b9