Malicious PDF — malware analysis report

Static analysis result for SHA-256 42086dd999dfb77f…

MALICIOUS

PDF

84.8 KB Created: 2021-08-10 17:01:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2aa7bcc4df760bf8feb301884f4b543d SHA-1: 0a199723ac8064d46c6d84901bd2c47ab3280c72 SHA-256: 42086dd999dfb77f3537e57c2b82363f385c219f6789f3dfcd3f6becb6f92b70
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to other PDF files hosted on compromised websites. This structure is indicative of a phishing or malware distribution campaign, where the initial PDF serves as a lure to redirect users to malicious content. The ClamAV detection and ML classifier strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://crewmak.ru/uplcv?utm_term=citra+3ds+emulator+pc+32+bit+download PDF link annotation
    • http://hockeydh.com/files/ups/files/fivepu.pdfIn PDF document text
    • http://vipnovini.bg/root/f/uploads/files/beribizitarepize.pdfIn PDF document text
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/761882c9d3ababce15c3b698c08162a2/jekebezusex.pdfIn PDF document text
    • http://websurin.net/UserFiles/File/43098337161.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/6b61e3178c4ec3e86aea0f35fb470015/wikazotipejugifolane.pdfIn PDF document text
    • http://ahchala.com/img/file/zagujakimibit.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16086a25df2d05---ralebutuxajuz.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/13df61e193b63cae0e266aebb7b45b0c/begafonemaxasapezi.pdfIn PDF document text
    • http://szakkepzosiklos.hu/upload/file/40067239955.pdfIn PDF document text
    • http://naviway.su/upload/files/dazaritizuvotavelo.pdfIn PDF document text
    • http://archissimo.eu/userfiles/files/xomenemalugurupizelo.pdfIn PDF document text
    • https://monyetmesum.com/contents//files/gubodonirilizubek.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/160d42e877fd0d---fanowebubedobakifelup.pdfIn PDF document text
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/f7cc3237ba0226a73c953aec3551a8ec/rakedilibolopixolefal.pdfIn PDF document text
    • http://arcenevents.nl/site/upload/files/xinudamorumemezewuwivopi.pdfIn PDF document text
    • http://solar-makernavi.com/ckfinder/userfiles/files/salimagenitowuwofabedosub.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/ji1jqg6gav4og5flv4ru9m7ls6/98590723176.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/fvp09st075tih733ag9f90m9ur/22254417206.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/160e4e76f92f44---25221812671.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/958fe7c1a42b8d41d0572c84e6f05979/zupajamalosoxajuzagaz.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609cafa9b0cd7---44648517046.pdfIn PDF document text
    • https://numberonerevolution.it/file/9983688867.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160c19cc0b499d---1279003177.pdfIn PDF document text
    • https://ankaratemizlikcim.com/depo/sayfaresim/file/9414668182.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c248bf9bead---farunav.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_off0000e36c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE36C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB83 11324 bytes
SHA-256: 13e76480a78f832aa237f41bb929bbc9cb301bc14956025505e04264bcb191d8
font_02_sfnt_off00011611.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11611 18196 bytes
SHA-256: 8853d7487658c56c1630f22449e0ecaeb8cda91e681b16c7a6e2242ce040ce2b