Malicious PDF — malware analysis report

Static analysis result for SHA-256 431fff901b19b4e7…

MALICIOUS

PDF

73.6 KB Created: 2021-09-12 10:11:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7c559bb8cc5dab6e3c8584beeb909592 SHA-1: d3afdd2d42aa2b4f7bde5ca73911085c0b6bbf00 SHA-256: 431fff901b19b4e77887b36351640df38db035e79d97c02888b37fe8af3d5ba9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely responsible for redirecting the user to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://huseyindurmuslar.com/images_upload/files/kiwuxo.pdf In PDF document text
    • http://aroma-es.site/yamituki-n/uploads/files/69037866813.pdfIn PDF document text
    • http://keletunderground.hu/images/uploaded_pics/file/kujenawibezelek.pdfIn PDF document text
    • http://e-sheremet.com/img/xarexunezus.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/40768433b67b4b59af7616c2d4743506/20105855537.pdfIn PDF document text
    • https://profipreklady.cz/www/ckfinder/userfiles/files/relebivuxarujepiweg.pdfIn PDF document text
    • https://arhstroi.by/uploads/files/89076893924.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16130c8e5c8237---parokuwigekuwok.pdfIn PDF document text
    • http://santiagoporter.com/js/ckfinder/core/connector/php/files/zefegibabidebatidanadifa.pdfIn PDF document text
    • http://almawred-sy.com/files/adminfiles/files/90140251232.pdfIn PDF document text
    • https://almavilag.hu/files/files/zowizoxebav.pdfIn PDF document text
    • http://cjmfgxfollow.morefriendship.com/upload/files/4488632325.pdfIn PDF document text
    • http://xinshifm.com/userfiles/file/55067065458.pdfIn PDF document text
    • http://ncfc.com.tr/ckfinder/userfiles/files/62630171980.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/57167508117.pdfIn PDF document text
    • http://xnucleus.com/members/member_images/files/3605708080.pdfIn PDF document text
    • http://polyalpan.hu/_user/file/ximil.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1612f99a6179b8---ketadovewitinipekojiw.pdfIn PDF document text
    • http://wpchkg.com/upload/image/file/mofebadapedibozinufi.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3fdb92e4f---pebusulidapan.pdfIn PDF document text
    • http://rajskiewakacje.pl/userfiles/file/jefetimafegatumixaka.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c44f49bf71---82602833268.pdfIn PDF document text
    • http://koszyczarek.pl/userfiles/file/50965067796.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=pre+calculus+11+textbook+pdfPDF 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_off0000bd41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD41 10904 bytes
SHA-256: 6d24d609da8808e6529ecc72fe55bafd5f0ccbe2feffbe64ce7c9cc42be4e851
font_01_sfnt_off0000d688.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD688 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE9A 16404 bytes
SHA-256: b580e101638dcda69deda263992434d7339db922a5c473d333ba4b7842a9783a