Malicious PDF — malware analysis report

Static analysis result for SHA-256 91a7ec77afcd3fbe…

MALICIOUS

PDF

104.0 KB Created: 2021-09-18 03:52:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 380a18ea79a5a99b8da2555f7c825e64 SHA-1: 8d97bb5be79c87d38f1aa6e440ce67942c2742c1 SHA-256: 91a7ec77afcd3fbe466cb8377d6f79935a9dc6f63bfe70cba66fbd93305338a8
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://cructi.ru/uplcv?utm_term=watch+the+late+late+show+online+free PDF link annotation
    • https://hotelite.in/userfiles/file/gunodinifi.pdfIn PDF document text
    • http://studiofranzoni.eu/userfiles/files/65039736740.pdfIn PDF document text
    • http://countryclaim.cz/userfiles/file/25065144720.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/vusimogizox.pdfIn PDF document text
    • http://kbfrutos.sk/images/_file/91581984856.pdfIn PDF document text
    • http://kidsjeodo.com/images/files/vewaludugepomalasiwinage.pdfIn PDF document text
    • https://hobbypet.cz/files/file/50143678765.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/36711142704.pdfIn PDF document text
    • http://rkenterprisesonline.com/FCKeditor/file/17889195371.pdfIn PDF document text
    • http://dasbluemchen.com/25210337884.pdfIn PDF document text
    • https://feltshoe.com/userfiles/file/sogusu.pdfIn PDF document text
    • https://ctcitsupport.com/media/files/konefoxafewevijozi.pdfIn PDF document text
    • https://bruceautoservice.com/files/file/nanuxotefisorovepipokik.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/16135eb4056f39---72567205026.pdfIn PDF document text
    • http://usairsprings.com/userfiles/file/61882428518.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/61746112303.pdfIn PDF document text
    • http://tzoetemondje.be/uploads/files/7252262587.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ce3bee40c8---tulezubewadiralesik.pdfIn PDF document text
    • http://gibkrakow.pl/uploads/files/14691284537.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613463b999327---tobelevo.pdfIn PDF document text
    • https://defi128.com/userfiles/files/totufubazawinoruxitisid.pdfIn PDF document text
    • http://tokyosushilohaus.com/uploads/files/foluzukafuz.pdfIn PDF document text
    • http://travelcenterpuntos.com/campannas/file/82823648831.pdfIn PDF document text
    • http://newbusan.net/FileData/ckfinder/files/20210917_93D8F451AB237EB3.pdfIn PDF document text
    • https://editions-tlp.fr/ckfinder/userfiles/files/fenejixidugiwigopavelev.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_off00012d4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D4A 10512 bytes
SHA-256: 22d5527459fce3662541b3134573474a5a6b452d70bf90ca282b7f9bdfeea24b
font_01_sfnt_off00014545.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14545 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015d57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D57 20052 bytes
SHA-256: 966e29bac08276f2e092c026f1428e2721e94e7c623d03ea57e781a12ff094c0