Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8f10fc7672a44ec…

MALICIOUS

PDF

68.4 KB Created: 2021-09-27 12:42:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 32a9b2d02ead8508cae0878aea177f2e SHA-1: b8bd9a94a8bec8f63eb0150f44545f4a86a72f9f SHA-256: e8f10fc7672a44ec89a5ac8af61aae43398ca573c234e2e237ef2dc60d4d9f6c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous external URLs pointing to potentially compromised or disposable hosting. The document body is heavily obfuscated, preventing analysis of its direct content, but the presence of multiple external links suggests a phishing or malware distribution lure. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://inwebjor.ru/uplcv?utm_term=how+to+watch+football+on+my+phone+for+free PDF link annotation
    • https://fundoohairstyles.com/hairstyler/images/file/71061847704.pdfIn PDF document text
    • https://marblobath.com/app/webroot/img/files/16322450455.pdfIn PDF document text
    • http://tiyuchangdi.com/upload_files/files/20210904_200310.pdfIn PDF document text
    • http://weldingplaza.com/files/file/4275516023.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/161479b05bf909---dugukozokukogakezakugivuv.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/80005524807.pdfIn PDF document text
    • https://firesystem.ro/imagini_ws/dinawenexilifora.pdfIn PDF document text
    • https://thietbixanh.net/uploads/files/donin.pdfIn PDF document text
    • https://pasarangroup2.com/contents/files/muxalisusifodimax.pdfIn PDF document text
    • http://specimport.by/files/files/14910614806.pdfIn PDF document text
    • https://nadrozmerne-sklo.cz/uploads/5615417422.pdfIn PDF document text
    • http://pc580.cn/upload_fck/file/2021-9-14/20210914183624412420.pdfIn PDF document text
    • https://lesrimaudieres.com/images/uploads/file/tisiwagogemevexusilolaje.pdfIn PDF document text
    • http://www.almansori-ye.com/almansorifiles/files/latejeninasubijupexeli.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/22645788410.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141afe9458ca---3927223496.pdfIn PDF document text
    • http://studioguagnoni.it/userfiles/files/fumalume.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/b843beea199765d731444428f5601efe/rililikusamajibinuzav.pdfIn PDF document text
    • http://qhzs88.com/admin/fckeditor_upfiles/file/2021090915175080554.pdfIn PDF document text
    • http://sjar-tech.com/uploadfile/file///2021090322515820.pdfIn PDF document text
    • https://watosaphotography.com/app/webroot/userfiles/files/20210911_115054.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/4ej14u0oovsol29ctr1fmka0mi/wejeb.pdfIn PDF document text
    • http://radiosalsa.fr/php/rs/filesupload/file/tukole.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_off0000ad76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD76 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c58d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC58D 10816 bytes
SHA-256: cf30bffd241b7a874de148bca1f8e5c048478538aa06d436fc2b519178737af9
font_02_sfnt_off0000de25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE25 15016 bytes
SHA-256: 75c879518a0aeb95c64881c6aba9c619f567302e77f60c7ed10307adb7b3a2dd