Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c392a7b838b6d12…

MALICIOUS

PDF

71.0 KB Created: 2021-09-26 08:41:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0c074ba588e63c3a17590fbd23dd36ee SHA-1: d303aac1e37eb19b4f6fa071d92ef4c9fc756380 SHA-256: 8c392a7b838b6d1288237bd98ada8750a5f2287ba02dcce4ce1809aefa0a605f
126 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm with numerous external URIs pointing to potentially disposable hosting, suggesting a phishing or malware distribution scheme. The PDF document body was heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and heuristic firings strongly suggest it is designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://0955205219.jwa.tw/userfiles/files/domodutuje.pdf In PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/161430e32943b3---60459109362.pdfIn PDF document text
    • https://eternalbliss.net/file/84398345735.pdfIn PDF document text
    • http://hyundai-baoloc.com/luutru/files/96555566088.pdfIn PDF document text
    • https://buildingexpertsdirectory.com/ckfinder/userfiles/files/divaxi.pdfIn PDF document text
    • https://www.artikel238.nl/emmwebbit/resources/ckfinder/userfiles/files/bevevibitizexo.pdfIn PDF document text
    • http://st-ark.it/userfiles/files/11189411808.pdfIn PDF document text
    • http://rebeccaosborne.com/uploads/lamosisi.pdfIn PDF document text
    • http://dominant.name/userfiles/file/wuwexatirudabepipam.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/gaxamej.pdfIn PDF document text
    • https://keyseries.us/userfiles/file/sasubuxakiminoz.pdfIn PDF document text
    • https://mexico-airport-transfers.com/ckfinder/userfiles/files/84489870298.pdfIn PDF document text
    • https://zapret-rf.org/web/img/podborky/files/pojafumatoxojuzifaj.pdfIn PDF document text
    • http://24cvety.ru/upload/files/rafug.pdfIn PDF document text
    • https://mudraconsultancy.com/uploads/files/57888849678.pdfIn PDF document text
    • https://viettrungson.com/media/Files/tekumudabo.pdfIn PDF document text
    • http://creativetechno.in/userfiles/file/94754828348.pdfIn PDF document text
    • http://lemma-studio.pl/userfiles/file/jivogelagevofupamemenetu.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/14303d28962fe98d229958327fbc30b2/mimex.pdfIn PDF document text
    • http://www.pethouse.es/ckfinder/userfiles/files/7027000750.pdfIn PDF document text
    • https://ylwlgwadmin.ylwl.cn/upload/files/55599590779.pdfIn PDF document text
    • http://didaconcept.com/admin/fckeditor/file/78087375810.pdfIn PDF document text
    • http://gamjagolla.com/uploads/files/pokuriduzejobasoviv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=hd+streamz+live+sportsPDF link annotation
    • 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_off0000b1e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1E5 16784 bytes
SHA-256: 91583ce38385685c0c0c719c82d876ba38325b021ff8194bdbb5573e6f1bea51
font_01_sfnt_off0000dc75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC75 10568 bytes
SHA-256: aa0d094d2d9f82fd8cec1d14048245940704c30dca22401bd9826129288c9d46
font_02_sfnt_off0000f48f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF48F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1