Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a4f3838dc5d5393…

MALICIOUS

PDF

82.8 KB Created: 2021-09-15 10:20:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 1b4e8e173b7de4ac5515938a05ad6708 SHA-1: 62c775b0c4b67e4a13461480ccb0bf7f5c3f4d82 SHA-256: 6a4f3838dc5d53936b24d96c19e29390cf190e89fc6277cad4baff8a977957b8
74 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to disposable domains. The ML classifier strongly indicates maliciousness, and the heuristic for a link farm on disposable hosting further supports a phishing or malware distribution attempt. The embedded JavaScript likely facilitates the redirection to these malicious sites, potentially for exploitation or credential theft.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 5

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://smidgel.ru/uplcv?utm_term=crossy+road+android+tv PDF link annotation
    • http://santamariamikado.com/uploads/files/kazawewonazepabebaru.pdfIn PDF document text
    • http://hftyby.com/upload_fck/file/2021-9-11/20210911102308725863.pdfIn PDF document text
    • https://minervatech.work/js/ckfinder/userfiles/files/kapefazawevinita.pdfIn PDF document text
    • http://pickup-ws.com/userfiles/files/firuzipafikutejijuw.pdfIn PDF document text
    • http://effekt-film.de/files/file/xizavajosogoki.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/16525592274.pdfIn PDF document text
    • http://freeorden.com/media/file/23287880863.pdfIn PDF document text
    • https://sanghvicranes.com/staging/media/80714746421.pdfIn PDF document text
    • https://gea99.com/ckfinder/userfiles/files/91888372882.pdfIn PDF document text
    • http://ramenzoni.eu/userfiles/files/23583569196.pdfIn PDF document text
    • http://hyeminshop.com/DATA/files/mukesiguki.pdfIn PDF document text
    • https://nutstudio.it/userfiles/file/ladazagak.pdfIn PDF document text
    • http://loscogliodifavignana.it/userfiles/files/53792912176.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614178612d47b---nekubanuvari.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/lojumukaxodexaludipira.pdfIn PDF document text
    • https://kaplaitalia.it/userfiles/files/84198087048.pdfIn PDF document text
    • http://baocaosudanang24h.com/uploads/image/files/tisane.pdfIn PDF document text
    • http://mosjob.ru/images/file/lebikezofo.pdfIn PDF document text
    • http://www.palmettoexpresslanes.com/system/js/back/ckfinder/userfiles/files/jewalosojet.pdfIn PDF document text
    • https://ensegun2.com/ckfinder/userfiles/files/75468784687.pdfIn PDF document text
    • http://shyjjc.com/v15/Upload/file/202198112243254.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613ce44c453b0---tegevo.pdfIn PDF document text
    • https://everestart.com/images/stories/file/77973646602.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/zelipev.pdfIn PDF document text
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/17911470969.pdfIn PDF document text
    • http://escuelasfutbol8.com/docs/files/witogila.pdfIn PDF document text
    • http://nandishoverseas.com/UserFiles/File/vamitozakubimud.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_off0000ddbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDBE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f5d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D5 10272 bytes
SHA-256: 75780cdb807362103317ec56b08de33078487559412240fb1f32286c24892cf4
font_02_sfnt_off00010d19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D19 18708 bytes
SHA-256: 5e0481997d2f6928df90e4364cacd6e577b9cda853eabd754199f3497d7792fe