Malicious PDF — malware analysis report

Static analysis result for SHA-256 37f2ba0c0e34b849…

MALICIOUS

PDF

93.1 KB Created: 2021-09-01 06:00:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 67527f627829b6bf5e4841a7c8a8525f SHA-1: 288e592069eab80a237a57ab09f0359d271906ef SHA-256: 37f2ba0c0e34b849b0fd0a9d0a4bec76957d9c4abb93bc551435adf228884ae1
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The document body is heavily obfuscated and unreadable, providing no direct textual clues, but the heuristic firings strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://flightshop.jp/images/blog//file/21650274954.pdf
    • http://quatanggiabao.com/images/uploads/files/bikebenu.pdf
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/7e61a7ade3b818009b66dbe824b71024/15890123875.pdf
    • https://agentcctv.com/userfiles/file/juwodejimokasutakin.pdf
    • http://nacyc.jp/Upload/file/63380868037.pdf
    • http://www.hangmandigital.com/files/file/4706023661.pdf
    • https://ibericadearmerias.com/file/dowazugovaguvupafararus.pdf
    • http://bielwod.com/userfiles/file/bowamonedibo.pdf
    • http://whatcanidoforyou.eu/publish/file/38660531563.pdf
    • http://myrbacken.se/login/ckfinder/userfiles/files/befunipegekow.pdf
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/72173920435.pdf
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/sius39tp2i10p3a6u9ri2ov7o5/pisadexitodawun.pdf
    • https://hpsoft.shop/upload/files/budiwofefoborawazodi.pdf
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/765ab590b964a0848ccb52fac9e87eda/mesawodevubolesujegudogo.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e2f6d9eb39---40243008425.pdf
    • http://xn--om2b25zm6igqb.com/ckupload/files/nakofexupuwobowawerawu.pdf
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074a14609fbd---xudeze.pdf
    • http://hi-techfiber.com/userfiles/file/pufamife.pdf
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075644c8e0e0---72998424129.pdf
    • https://matao.ro/app/webroot/files/userfiles/files/wezorupuzerawikob.pdf
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/ac299fd61a4064cdf75f308c7f8f8722/gonipefe.pdf
    • https://z87992961.com/upload/files/20210718103343.pdf
    • https://baxsporthorses.com/userfiles/file/42215673460.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e0c358a68a0---48467263123.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=1969+ap+calculus+ab+section+1+answers
    • 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_off0000fced.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCED 16792 bytes
font_01_sfnt_off00011504.bin
14591402f99dda9b9f3c07f7b1214b2950a0ef690defac0dd59ac7f50ec8726b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11504 10984 bytes
font_02_sfnt_off00012e76.bin
08020e221f40e96a1bb5163388e50c5851845bd3b9175f17db1ddc05967b9b60
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E76 20768 bytes