Malicious PDF — malware analysis report

Static analysis result for SHA-256 cebbb7d6c7f85cc2…

MALICIOUS

PDF

80.7 KB Created: 2021-10-18 12:04:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 135b53be98e48b4231c3252a978b4019 SHA-1: 5a31fe39334fc7d1aee2a1ee0e700532c93de30b SHA-256: cebbb7d6c7f85cc211cdf62c3de935a33feaeb7d3c2bb1769d0c35c34ca6d3b6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm directing to multiple websites, many of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded URLs suggest a tactic of using link farms to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ecb30389b4---83899086499.pdf In PDF document text
    • https://pharmawell.eu/ckfinder/userfiles/files/morurewegunig.pdfIn PDF document text
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/69528916272.pdfIn PDF document text
    • http://defhjdrjioo.friend-match.com/upload/files/26372945733.pdfIn PDF document text
    • https://tele-video.ru/upload/files/munotexopelidegaj.pdfIn PDF document text
    • http://petgears.com/app/webroot/files/file/tojosidorubub.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/7b0c662929c316ddca9006e7e7f3e440/75856426076.pdfIn PDF document text
    • http://studiovalentini.eu/userfiles/files/27989393376.pdfIn PDF document text
    • https://slide-bearing.com/d/files/63996705264.pdfIn PDF document text
    • http://aesg2edcv.handylover.com/upload/files/fipudobubozixexav.pdfIn PDF document text
    • http://korytnica.net/data/files/junufepobufebusagunopuli.pdfIn PDF document text
    • http://www.pethouse.es/ckfinder/userfiles/files/moviruw.pdfIn PDF document text
    • http://mirai-kankyo.com/userfiles/files/11333706243.pdfIn PDF document text
    • https://dnm.tw/uploads/files/202109122007252463.pdfIn PDF document text
    • http://huiking.cn/uploads/file/211804298512.pdfIn PDF document text
    • http://italiangreyhound.pl/img1/userfiles/file/29632313681.pdfIn PDF document text
    • https://demo-calson.garment-pro.com/ckfinder/userfiles/files/76654762476.pdfIn PDF document text
    • http://www.synagoge-stommeln.de/ckfinder/userfiles/files/tizeragudomutusu.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161495ef81de81---65828036211.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/qfa4tffr17m4hbph9109o3l1vp/13718660983.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614361624c049---fifexixozetitoga.pdfIn PDF document text
    • http://scbczy.cn/up_files/file/20210906_123607.pdfIn PDF document text
    • https://office-agglo-larochelle.fr/userfiles/file/49791539081.pdfIn PDF document text
    • http://jujucuisine.com/userfiles/file/rorodefegunokokiduziku.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/RC0zOYPQW8A/uplcv?utm_term=ultimate+guitar+chords+and+tabs+pro+apkPDF 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_off0000d5fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5FD 11300 bytes
SHA-256: 7b17c686bb171f8021d2e755b84b1238840cba4feb6e904f59a26accf8e87d02
font_01_sfnt_off0000efe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000107f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107F2 17392 bytes
SHA-256: 0af1de349f863240bdf4e93e8e4f98cb91aa724e41d3961861dd42b6364f234f