Malicious PDF — malware analysis report

Static analysis result for SHA-256 c014fcbc3f546434…

MALICIOUS

PDF

68.8 KB Created: 2021-09-27 11:15:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 13866f329857a05adec586846e27da73 SHA-1: 63628cbf6f1d3f04ad13f5e01a8ee1974157849f SHA-256: c014fcbc3f546434cb99b90ff9d76a54de5f68e2893d5323c529c794c4eeba84
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised WordPress sites, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent, classifying it as a phishing trojan. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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 https://krisoc.ru/uplcv?utm_term=ram+test+android
    • http://studioarclab.eu/userfiles/files/39993819788.pdf
    • http://christ-china.com/filespath/files/20210927125610.pdf
    • https://stancijanegrin.com/UserFiles/files/94995971418.pdf
    • https://linhquan-group.com/upload/ck/files/kodufobuzenofubojuji.pdf
    • http://rejs2013.cycling-recycling.eu/imgturysta/files/sezudujikopedak.pdf
    • https://songod.vn/uploads/image/files/xotigezolebovujojo.pdf
    • http://abarappresentanze.it/userfiles/files/keribubatomi.pdf
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fe8c73cfd0---wijidadefeduxareviram.pdf
    • https://crownprolaw.cn/userfiles/Proj_Name/files/minodo.pdf
    • http://studiotecnicomaglio.it/userfiles/files/kanud.pdf
    • https://kopari.hu/files/file/90492639520.pdf
    • https://betenagro.com/sites/default/files/file/1836359071.pdf
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/4b8377242d7de77584298f5c2df6ee4f/14821176241.pdf
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614810041639e---51442030810.pdf
    • https://ski-valloire.com/ckfinder/userfiles/files/51461016093.pdf
    • https://willmarareachamber.com/ckfinder/userfiles/files/19781848068.pdf
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/122b735672d30450cf6534b93b5136b2/pupowabigususedegenu.pdf
    • https://hram-uspeniya.ru/ckfinder/userfiles/files/83914848226.pdf
    • http://kkslavicin.cz/sites/default/files/file/44565408259.pdf
    • https://maharajganjtimes.com/assets/ckfinder/core/connector/php/uploads/files/59297700937.pdf
    • http://harc-ias.vn/Images_upload/files/71292802221.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_off0000af86.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xAF86 16792 bytes
font_01_sfnt_off0000c79d.bin
bf14cc6a98237be589c75954577fb2d42dc799eec12caab03ee3fbfc5fb07504
pdf-font-stream PDF embedded font (sfnt) at offset 0xC79D 10408 bytes
font_02_sfnt_off0000df2a.bin
6f217810a60da063d068f783c0084a4c4bb294569caec5a9c129202cdbb0b5ba
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF2A 15344 bytes