Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a5b6ad3519c031b…

MALICIOUS

PDF

69.5 KB Created: 2021-09-12 11:52:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: bd4162a18a339a0bb83b30edd094be03 SHA-1: 533e82d2c88785b6816df3e6d9074a36b820298b SHA-256: 4a5b6ad3519c031bf02ea57830d4955d44bc39e6fb14187f724b0161991fb5f0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of numerous external URIs, many of which are part of a link farm, suggests a phishing or malware distribution attempt. One notable URI, 'https://catamma.ru/uplcv?utm_term=android+plugins+download', directly implies a lure for downloading potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://catamma.ru/uplcv?utm_term=android+plugins+download PDF link annotation
    • http://montagnobozzone.it/userfiles/files/27038913302.pdfIn PDF document text
    • https://optimuselearningschool.com/learning/site/images/uploadfiles/68297339121.pdfIn PDF document text
    • http://www.pes.edu.mn/ckfinder/userfiles/files/lotutakadesovedezirajuk.pdfIn PDF document text
    • http://printrun.nl/userfiles/files/30396653327.pdfIn PDF document text
    • http://eqletstalk.com/uploads/files/202109121033169172.pdfIn PDF document text
    • https://magnettoptan.com/upload/ckfinder/files/11688982930.pdfIn PDF document text
    • http://dep14kirov.ru/userfiles/file/27883373248.pdfIn PDF document text
    • https://biorenta.lt/ckfinder/userfiles/files/6611951247.pdfIn PDF document text
    • http://xn--76-6kca8aqc6c.xn--p1ai/pic/userfile/30167482790.pdfIn PDF document text
    • http://xn--80aafbladvtgxneccoge3bt.xn--p1ai/pict/file/43962637949.pdfIn PDF document text
    • https://libyamonitor.com/sites/all/libraries/ckfinder/userfiles/files/5694081486.pdfIn PDF document text
    • http://pillshop.ru/uimg/files/71655808182.pdfIn PDF document text
    • http://lednotice.com/userData/board/file/nutagonepepa.pdfIn PDF document text
    • https://forumhrdbekasi.com/webroot/userfiles/files/99231249223.pdfIn PDF document text
    • http://zulassung4you.de/bilder/file/legux.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613835134d5cb---33167051067.pdfIn PDF document text
    • http://ceraunavoltapizzeria.it/userfiles/files/ravononopogagi.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/siginutefosemibigazunek.pdfIn PDF document text
    • http://beerskiboot.de/img/upload/file/48463752973.pdfIn PDF document text
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/79222269794.pdfIn PDF document text
    • http://xn--80ab1a9a.xn--p1ai/sadm_files/kilufosubakuwopujukodin.pdfIn PDF document text
    • https://questyme.com/userfiles/file/85084512354.pdfIn PDF document text
    • http://aodaibooking.com/FileData/ckfinder/files/20210910_80DB74BABB87855E.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/16130626226c08---wabenejiwefa.pdfIn PDF document text
    • http://hurtmar.pl/Upload/file/1417149764.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_off0000b455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB455 14464 bytes
SHA-256: a7ad2adc661994922e2e2647ac62c5bc93c8434f0df53f433d988f7187941f2c
font_01_sfnt_off0000d84c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD84C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f063.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF063 10504 bytes
SHA-256: 64a943220dad305a0ced8978c344860933aa97f2301931cb0f514cc451213435