Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b9ba70eb3975008…

MALICIOUS

PDF

81.8 KB Created: 2021-06-30 06:11:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 1951eed566fda91fb7e0fa1f2a2e9453 SHA-1: 23d8bda2a4d42a903522d5f493434e39402f4de0 SHA-256: 5b9ba70eb3975008b9093d0036ef1045f0b14eb40d5df0a1ea715f7c8f4ef021
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to compromised WordPress sites and other domains, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics and the compromised CMS upload link heuristic strongly indicate that the primary purpose is to lead users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://philabc.ru/uplcv?utm_term=pcb+file+to+pdf+converter+online PDF link annotation
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086edf6ae06d---85447821056.pdfIn PDF document text
    • http://roland-toys.eu/userfiles/file/77641321596.pdfIn PDF document text
    • http://overtonnation.com/clients/f/f9/f97855507a39dfa58978186db9bff07a/File/66014698776.pdfIn PDF document text
    • https://cornerstonelaw.eu/userfiles//file/lejapakolawakuruburu.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/131fpbo04ua6l5qbbt8509seg1/61611544755.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d82445f79a---nugarawunaguji.pdfIn PDF document text
    • http://mientrungland.net/uploads/image/files/18190538403.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/renuzaxorofob.pdfIn PDF document text
    • https://magerp.org/upload/files/famafezabalulesub.pdfIn PDF document text
    • http://goergenpainting.com/clients/0/0d/0d1038892961fdbf96b6a8e7e8daca8f/File/zukofewujetuxozewiluliwex.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/83526092a407325477969fa7338812e2/lipedawokafowolofa.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/fbc10c171b2fc778e35f024bd6566930/sogop.pdfIn PDF document text
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/6d1334506daf694cd4530edacec96f9d/71415042034.pdfIn PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/ipavpd5ed6tv3jr9t7iqc98tvt/18304706927.pdfIn PDF document text
    • http://thucphamchucnangmy.vn/uploads/files/86450891257.pdfIn PDF document text
    • http://szyldkj.com/luodan/images/userfiles/file/74864970018.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a99ae07b2f5---lizisowenijanajaseja.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd63f31f8d3---lorivewiwaxejelanofeke.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/32155cb3657eb1ede31952de3d453597/88494551640.pdfIn PDF document text
    • https://adasms.fr/userfiles/file/58693867061.pdfIn PDF document text
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fae9a72796---9334111096.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/ad1069216fa7a08849d08ce2ece9c0a7/timelimojotanojejakagiz.pdfIn PDF document text
    • http://interwork.sk/userfiles/file/16982150935.pdfIn PDF document text
    • http://erbamedica.org/userfiles/files/pisojatoborixowolilubeko.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/9527b24d6db3f39bc628c29532651cb5/karolumupuwusozoxodu.pdfIn PDF document text
    • 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_off0000ddbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDBC 10492 bytes
SHA-256: 6b2d3d51373650d5fce86dc9d8d4eb8e55e009bc1de4e1d31e04d2a8f1f4538b
font_01_sfnt_off0000f571.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF571 17072 bytes
SHA-256: 55c1ec6c2cb23f660489505395f07358cbbc8c02082e6a157aecfbe1532e9114
font_02_sfnt_off000121f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1