Malicious PDF — malware analysis report

Static analysis result for SHA-256 891c163cb47834ac…

MALICIOUS

PDF

89.3 KB Created: 2021-07-09 01:24:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f810937cffd47fdb6560704bb6164018 SHA-1: 0fa134bf91880cd2030301927914e06077f71e95 SHA-256: 891c163cb47834aca3ec809bf6e558c8a14b7f81137526665cf54f78470f5f98
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to numerous other PDF files hosted on compromised WordPress sites and disposable domains. This pattern is indicative of a phishing or malware distribution campaign, where the initial PDF serves as a lure to redirect users to malicious content. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://bukvoznaika.ru/ckfinder/userfiles/files/biwun.pdf
    • https://t2sc.me/userfiles/vanapowafupulezowilunite.pdf
    • http://atya.eu/files/file/31443427088.pdf
    • http://vinhhangvien.com/upload/files/42515240481.pdf
    • http://magendans.com/imagefiles/file/lasopo.pdf
    • http://toyotalongbien.org/data/dulieu/files/59660710395.pdf
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/d214223edf632d87b9e97cd11ba5f73e/nofit.pdf
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/839f09aa360da341c5fe8f61d0da84e3/miwugor.pdf
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/160acdaa5e5da8---28001007299.pdf
    • https://netron.pt/app/webroot/media/files/bovivolojife.pdf
    • https://seerupit.dk/assens/file/wuxiram.pdf
    • http://clarkstownhs64.com/clients/2/25/255c49a504cbad61718694d8b78dfcdd/File/96374180361.pdf
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/suu7ia7io5ov5npng2uatua94j/jures.pdf
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/d30f82314099f507d0436bd957371fd9/patab.pdf
    • http://piazzademarini3ge.com/userfiles/files/2256392296.pdf
    • https://burmesecatclub.nz/wp-content/plugins/super-forms/uploads/php/files/54d6ef0d1f74f71f45cde512606a5d22/pezobitegupigawojisunoweb.pdf
    • http://firstcuwire.com/file_media/file_image/file/kesugojajukomavegosiwuwu.pdf
    • https://cpsguffanti.com/uploads/file/giweketejamofamisan.pdf
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4b871e3113---17845569377.pdf
    • http://timebank.ru/sites/default/files/photos/pagefile/6683458501.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160732f6343b0c---kizutekowexakakumapedawi.pdf
    • https://hotelindigha.com/FCKeditor/file/durowenume.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0305cddca---14648464346.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=melodic+trance+2020
    • 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_off0000eccf.bin
fbcafcc610db6fa87334dac7980c91e4fc26afd0b19246ca4505295d943a18b6
pdf-font-stream PDF embedded font (sfnt) at offset 0xECCF 23820 bytes
font_01_sfnt_off0001281b.bin
0c0140abc112506c95543b8e43abeace81735a32a06bc39de78c8dd15f293773
pdf-font-stream PDF embedded font (sfnt) at offset 0x1281B 10428 bytes
font_02_sfnt_off00013fdd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13FDD 16792 bytes