Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6a5ba172368efbe…

MALICIOUS

PDF

68.8 KB Created: 2021-09-26 03:23:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d4d1f7ba9a39bb50a31ab948dd9dd502 SHA-1: c77bffb3504bd0e2a5590b902147f9cff562c420 SHA-256: b6a5ba172368efbed985863454e3d36da7c36bf3fb8cad8c769e637726453e44
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to external domains, characteristic of a link farm used to distribute malicious content or phish for credentials. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the assessment of a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://pistant.ru/uplcv?utm_term=obb+file+download+pubg+mobile
    • http://9jamail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/12492050415.pdf
    • https://777mto.org/contents/files/54359943935.pdf
    • http://akkoryazilim.com/userfiles/file/5999647066.pdf
    • http://xn--80aafmoni2biho.xn--p1ai/admin/ckfinder/userfiles/files/giguxinezuga.pdf
    • http://rrarental.org/upload/file/27103943340.pdf
    • http://langeline.com/ckeditor/upload/files/84115609979.pdf
    • http://whitedwarf.ru/public/images/ckfinder/files/2818755560.pdf
    • https://doanandieuduong295doson.vn/namthuan/images/news/files/zuwenosep.pdf
    • http://jamesandsons.ca/userfiles/file/9603551541.pdf
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/0kibucfbfv3bg6di7dqmev6aem/lijedobudufa.pdf
    • http://faw-asia.com/image/upload/files/45253154454.pdf
    • http://greenbiotech.vn/uploads/userfiles/file/luxigisaxamegajazorita.pdf
    • http://pujcovnanaradi-tvarozna.cz/userfiles/files/34631008695.pdf
    • https://businesslife.com/content/files/44558764419.pdf
    • https://gloriamus.org/Uploads/userfiles/files/18273443986.pdf
    • http://customize.fr/fckeditor/editor/filemanager/connectors/php/img/Editor/file/gasevonokexobepimevakulu.pdf
    • https://roarmysecurity.ro/mm/file/kapiwi.pdf
    • https://blsautomation.com/ckfinder/userfiles/files/54720469092.pdf
    • https://thai-airpark.com/ckfinder/userfiles/files/tujavijinelofumof.pdf
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/16140b333da0a5---3536066380.pdf
    • https://sokolzgierz.pl/web/uploads/files/4265779427.pdf
    • https://venefoil.com/ckfinder/userfiles/files/tanajujamegurufixi.pdf
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/dewoxapujixapixat.pdf
    • http://songpinhao.com/userfiles/files/55210269357.pdf
    • http://csc025.com/userfiles/file/20210926064253_lgmo00.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b074.bin
8c7e17dd1fc606ea7d3a638968c93e4b2347afe8f85b7cd4a1ed490f8199019f
pdf-font-stream PDF embedded font (sfnt) at offset 0xB074 10824 bytes
font_01_sfnt_off0000c8f9.bin
783aac9c075de7647cd91911f6c828377d61a3a6fdfb4137bdfbb661fd5e02c6
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8F9 14688 bytes
font_02_sfnt_off0000edbd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDBD 16792 bytes