Malicious PDF — malware analysis report

Static analysis result for SHA-256 8788de745665f45e…

MALICIOUS

PDF

75.8 KB Created: 2021-09-16 23:44:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: db8f4b54f92cc449f3a57e2da7be84b9 SHA-1: 4dbe5aeea04ae8cbb3c00afe97bbe91d996f1d8b SHA-256: 8788de745665f45ef07aa3f97dd391b4bb50b5572943bc4b4a502ce39309755b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including ML and ClamAV, indicating malicious intent. The presence of numerous external URIs, many pointing to disposable hosting and exhibiting link farm characteristics, strongly suggests a phishing or malware distribution campaign. The document body is heavily obfuscated, preventing a clear understanding of its direct content, but the overall structure and embedded URLs point to a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://synerhu.ru/uplcv?utm_term=my+talking+angela+christmas+update PDF link annotation
    • http://soupworld.de/upload/file/9241887747.pdfIn PDF document text
    • https://culturasiapamplona.com/guiarte_userfiles/files/27299687128.pdfIn PDF document text
    • http://ortopediaszombathely.hu/editor_up/49155504107.pdfIn PDF document text
    • http://zechnerbau.at/images/content/files/80663935594.pdfIn PDF document text
    • https://mkycc4.com/kycc4.com/userfiles/files/87362341476.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/xaxotaz.pdfIn PDF document text
    • https://digireg.ru/upload/zevira.pdfIn PDF document text
    • http://feuerwehrobrigheim.de/upload/files/2338611628.pdfIn PDF document text
    • http://excitechem.com/userfiles/file/mivuposibufopiwawapuxi.pdfIn PDF document text
    • https://oazapiekna.com/zdjecia/fck/file/ritogoko.pdfIn PDF document text
    • http://clinicaveterinariamontecchia.com/userfiles/files/79192194648.pdfIn PDF document text
    • http://www.cda.org.hk/ckfinder/userfiles/files/viripepaba.pdfIn PDF document text
    • http://architettorobertafasola.eu/userfiles/files/3130409442.pdfIn PDF document text
    • http://www.ecrivains-consult.fr/easyonline/ckfinder/userfiles/files/7182956726.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ef9353b2ba---xunuzopen.pdfIn PDF document text
    • http://bettynblue.com/upload/fck_img/20210902/file/26179430592.pdfIn PDF document text
    • http://lucchetta.net/userfiles/files/jizikutiwujodaxale.pdfIn PDF document text
    • https://malayalamfoundation.org/admin/my_files/file/95976565639.pdfIn PDF document text
    • https://nhahangthanghuong.com/uploads/files/41826611683.pdfIn PDF document text
    • http://leruichem.com/upload/files/92482021287.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_off0000c083.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC083 18296 bytes
SHA-256: 1f94b136f5c15eda0f510ed9298c7765df11a9706afb7e78768df708f1997498
font_01_sfnt_off0000f06f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF06F 11140 bytes
SHA-256: 76b70f773bd58ed475bee2426f6ef27b74c9a0e9bb70fa93d84402f34a427b59
font_02_sfnt_off00010a0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A0C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1