Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff31b33ae3617014…

MALICIOUS

PDF

75.6 KB Created: 2021-08-25 12:13:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-23
MD5: faec5e67a03717b275e479cf731179c4 SHA-1: 42c5ad14012638fe02ec2dd2deb9379518329574 SHA-256: ff31b33ae3617014d6d55f9b877dba416bfbdca4db7d5c8e322fdc9eaa4d25e4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

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://boxethai38.com/upload/file/44645026362.pdf In PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098f3d47074a---1363655242.pdfIn PDF document text
    • http://vuatoyen.com/uploads/userfiles/file/xetobuxifukogudod.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/89867892239.pdfIn PDF document text
    • https://advance-pack.com/editor_upload/file/27187898320.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083fd8f81e8d---80754616308.pdfIn PDF document text
    • https://ecodiagnost.com/ckfinder/userfiles/files/sirepagazono.pdfIn PDF document text
    • http://isvpro.com/custom/files/guwebabavomofiwuvota.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/64e411c5adcee0f716e8a76a29560ba9/mitupogirekozowelebodoz.pdfIn PDF document text
    • http://www.ville-dammarie.com/ckfinder/userfiles/files/9211143983.pdfIn PDF document text
    • http://tunglamgarden.com/images/fck/file/lifetadeva.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160db23b884525---retiverupatirunawo.pdfIn PDF document text
    • http://sjar-tech.com/uploadfile/file///2021072419413850.pdfIn PDF document text
    • http://sakaryakasaplarodasi.org/userfiles/file/wulofubenexon.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/476s8955q36qao535oogqrrrp6/57796546467.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/44225817974.pdfIn PDF document text
    • http://revucue.com/ckfinder/userfiles/files/14521688253.pdfIn PDF document text
    • http://feynburg-uhren.de/uploads/ninep.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094fa190d3e0---24629647001.pdfIn PDF document text
    • https://korovin.org/site/img_ufiles/318025720.pdfIn PDF document text
    • http://cupta.org/userfiles/files/20210526185036.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=meaning+of+delusional+heartPDF 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_off0000c79b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC79B 15820 bytes
SHA-256: 1e4261b02237a5fbd86d1a22b4f2da9091c8a4643bf06a42ae56c39ca98dc312
font_01_sfnt_off0000f0ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0CE 10724 bytes
SHA-256: cdf03978794bf2312f167121ac6acad6d465ebbdb6b2b1da03ec59a60d85d9de
font_02_sfnt_off0001092b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1092B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1