Malicious PDF — malware analysis report

Static analysis result for SHA-256 2951579cbca4a7f1…

MALICIOUS

PDF

81.7 KB Created: 2021-09-19 12:10:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 193a60ac944afc07ef07ee718ac4808c SHA-1: afba268a66a7a0f4ea3ef014a397f4c67ae83b29 SHA-256: 2951579cbca4a7f150ace5e2c0e4530957d35ee609fd29c205914dc48ff26f14
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload storage, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

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://medvor.ru/uplcv?utm_term=avatan+app+download
    • https://ksi-system.pl/editorfiles/file/wavinome.pdf
    • http://3suntech.com/UploadFile/file/20210902124448649.pdf
    • https://markyatirim.com/resimler/files/darum.pdf
    • https://at1-turbo-j3t.com/contents/files/matarobugudikiki.pdf
    • http://clingac.es/d/files/bufosidito.pdf
    • http://caminodesantiagoenmoto.com/assets/ckfinder/core/connector/php/uploads/files/43293186061.pdf
    • http://nemeckystrakac.sk/editor_uploads/files/7614900648.pdf
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143adad62e79---25329346279.pdf
    • https://datatech-int.com/userfiles/file/59555649404.pdf
    • https://www.akilciilacdernegi.com/ckfinder/userfiles/files/83224080563.pdf
    • http://lso-msm.com/userfiles/file/39027723118.pdf
    • https://korzayithalat.com/spot/admin/fckeditor/userfiles/file/vemasa.pdf
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130c5c8219c4---36614213657.pdf
    • https://my-natural-style.net/upload/files/63895540358.pdf
    • https://equimat-cheval.fr/file/xakobixitufar.pdf
    • http://boldogelet.hu/media/96452092202.pdf
    • http://abwingstop.com/uploads/files/vekunikep.pdf
    • http://starcity-vinhomes.vn/app/webroot/img/files/mopomuzufoxolixexo.pdf
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/770963c5a9f2174de1a8f3bd59f462f7/xomazi.pdf
    • http://protezas.lt/i/File/70916450787.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141638a2bb2c---71198810245.pdf
    • http://leasingtowers.com/ckfinder/userfiles/files/pibes.pdf
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/60e303f5cf2310242b2227865b3a165a/lokifimuduzalekufubipubis.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_off0000dc75.bin
438dc2dd1ea307f77e29fd3590021da2112112bc57883d48407c9902f89ad79a
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC75 18196 bytes
font_01_sfnt_off00010ad9.bin
414460f9c5707e37d11fd3080ba0e60fe579bb48d2569f48a7c3a59e3d7de905
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AD9 10028 bytes
font_02_sfnt_off00012147.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12147 16792 bytes