Malicious PDF — malware analysis report

Static analysis result for SHA-256 31b9017e4406f9c2…

MALICIOUS

PDF

74.7 KB Created: 2021-09-12 22:46:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 4382c00e879430569e506bd3a797fb62 SHA-1: c01a3ad40dbccde65c2cbccb2141216cef72a0a1 SHA-256: 31b9017e4406f9c21e416f86eb6e17b59abb01bc6510553ebd3de42588b40cda
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to a link farm, a common tactic for phishing or distributing further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and embedded links suggest it's designed to redirect users to potentially harmful sites, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://alrehabourhome.com/userfiles/files/62170703887.pdf In PDF document text
    • https://rimi.sk/userfiles/file/tegutut.pdfIn PDF document text
    • https://nguyenvanhuongloc.vn/app/webroot/files/images/pages/files/28308709741.pdfIn PDF document text
    • http://domuran.pl/files/file/ruxusegibawonat.pdfIn PDF document text
    • https://commonwealthsportsawards.com/userfiles/file/90983044419.pdfIn PDF document text
    • http://w.scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/gokinenik.pdfIn PDF document text
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16130322ccf038---vanafezamuzofawove.pdfIn PDF document text
    • http://meandnetworking.com/ckfinder/userfiles/files/35359073552.pdfIn PDF document text
    • http://ktcyy.com/ckfinder/userfiles/files/45638887832.pdfIn PDF document text
    • https://allianztc.ro/files/file/pixuxiso.pdfIn PDF document text
    • https://boucherienabli.com/uploads/FCK_files/file/pololazozilonibifizun.pdfIn PDF document text
    • http://ymjgolf.com/file_media/file_image/file/lofuvijikuzigobazazugus.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/98595353375.pdfIn PDF document text
    • http://khyljg.com/uploadfiles/files/83911828255.pdfIn PDF document text
    • http://carzip.biz/files/uploads/files/8138919156.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/4g9p94l1nhq9sd3mg8fcooav0q/xemere.pdfIn PDF document text
    • http://ssteelelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gaxusafaxusisasaz.pdfIn PDF document text
    • http://lungshingcentre.com/userfiles/53684606703.pdfIn PDF document text
    • https://premium-house.uz/images/file/80753079040.pdfIn PDF document text
    • http://phongkhamthienhoa.vn/images/files/2037467090.pdfIn PDF document text
    • http://custom-mugs-factory.com/uploadfile/files/rufelavawubejevovejiva.pdfIn PDF document text
    • http://eva.am/files/65fe59959b1d7269.pdfIn PDF document text
    • http://bouwbedrijfbouwheer.nl/userfiles/file/jofigedu.pdfIn PDF document text
    • http://salocchi.it/userfiles/files/77193184789.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=prayer+thanking+god+for+his+faithfulnessPDF 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_off0000c068.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC068 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d87a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD87A 17196 bytes
SHA-256: 7ad884e425d41c67c9c1ec9c655278f0e3c068ac874324d6e644da8d15e92f5b
font_02_sfnt_off00010488.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10488 10940 bytes
SHA-256: 016bcd6c411559adb145552ae1b7b69462bd8fce1ea6b9a1a58f27dc1742e657