Malicious PDF — malware analysis report

Static analysis result for SHA-256 6656f30867dbe3c9…

MALICIOUS

PDF

76.0 KB Created: 2021-09-18 10:08:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 367107206ecea91efbe481a8b4d97c0d SHA-1: 66c728a204358f1716ecc5b6571f79f75bf0a967 SHA-256: 6656f30867dbe3c906908638b9072245234948db6ef8fe07be8e7fd55dcf2f23
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics and link farm indicators strongly supports a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://crewmak.ru/uplcv?utm_term=truck+loader+3+friv
    • http://polyalpan.hu/_user/file/jadup.pdf
    • http://aktifimmo.lu/userfiles/files/71001639475.pdf
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/b1bj2igcrq8vqpgdmt8qcj9g6q/gulanafunudurigonobu.pdf
    • https://senegal4d.com/contents/files/bofetigezuziwadevati.pdf
    • http://ljsmelt.com/upload/files/76946183957.pdf
    • https://pingthye.com/userfiles/files/78571236471.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd0b07076f---79934530204.pdf
    • https://moulindelarroque.com/userfiles/file/dinijizi.pdf
    • http://huyndaicaudien.com/upload/files/22030653609.pdf
    • http://dorisemitchell.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xatibizad.pdf
    • http://www.hermosabeachbungalows.com/userfiles/files/dofowoteritavamexobobipi.pdf
    • https://dananeye.com/uploads/files/202109022115423183.pdf
    • http://konferencii.org/web/uploads/assets/file/11180661402.pdf
    • http://rococosofa.com/files/files/dajebosixelorutebi.pdf
    • http://bladensburg.abwingsmd.com/uploads/files/dewagifuretulutozu.pdf
    • http://generale-bureautique.fr/gdb/files/file/39356681931.pdf
    • https://dimensionshoppe.com/alpha/ckfinder/userfiles/files/tivetimesifosagiwijunuk.pdf
    • http://resetimpianti.it/reset/public/file/pugugidozarat.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/161363f36ef4a7---68518280599.pdf
    • http://polaryachtmanufactory.com/res/wysiwyg/file/wetamil.pdf
    • http://www.azurwelcomeservices.com/userfiles/file/48419846706.pdf
    • https://www.la-melodie-des-saveurs.fr/ckfinder/userfiles/files/daxomulonorenevoju.pdf
    • http://111-orte.de/testarea/cwsCMSlight/media/files/kevogaguke.pdf
    • http://ugrctrani.it/userfiles/files/21441660154.pdf
    • https://estudiowebcolombia.com/ckfinder/userfiles/files/fipoja.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ba72.bin
cfd37065cad35b5494ce935a58dca021931cf14171162f0ec0a74d1f9b1be798
pdf-font-stream PDF embedded font (sfnt) at offset 0xBA72 10492 bytes
font_01_sfnt_off0000d279.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD279 16792 bytes
font_02_sfnt_off0000ea8b.bin
cba9bd33f080b3d685cd55f0678a8383f5d808a513ab2a649ded886a661d97ef
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA8B 21492 bytes