Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd475cd80fdc453c…

MALICIOUS

PDF

76.5 KB Created: 2021-09-14 01:54:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ca4aaac456eb3c32931057789c25dc07 SHA-1: 5e64dc02a6d4ea4408523c4bed70edae00970ed0 SHA-256: cd475cd80fdc453cc705e30b5a371305de36c5c1c5f40da3c432b6614fedd25d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm pointing to various PDF documents hosted on multiple domains, some of which are identified as compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. The presence of numerous external links suggests an attempt to direct users to malicious content or further stages of an attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://ku4ysk-9lgp4y.com/contents/files/rugijexozazabigilebodiwi.pdf
    • https://sogelec-eng.com/files/ckfinder/files/72713004290.pdf
    • http://rulife.ru/ckfinder/userfiles/files/16569140156.pdf
    • http://cuacuonductudong.com/upload/files/46061780752.pdf
    • https://textmakareknutsson.se/upload/image/vimasisufugoxu.pdf
    • https://namratalakhotia.com/userfiles/files/kewomuz.pdf
    • http://bjdfszwy.com/filespath/files/20210910093849.pdf
    • http://bangladeshceramicsociety.com/uploads/editor/files/tixekakaxalirumu.pdf
    • http://hoteldazegliotorino.com/userfiles/files/pavije.pdf
    • https://traveletrust.com/basefile/traveletrustcom/files/kaguvogakuguwuwosu.pdf
    • https://architektor.ru/uploads/file/12877405248.pdf
    • http://hengtongrongshang.com/jingkelun/userfiles/files/20210914061232.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/7d3774a5c80815133710e26c26e452e2/jutakumizubidivaguwibap.pdf
    • http://odontoflash.eu/userfiles/files/dumexuferogiluvananige.pdf
    • http://digjamaica.com/app/webroot/files/47112863015.pdf
    • https://www.tvmreza.tv/ckfinder/userfiles/files/98846018265.pdf
    • https://asiantms.com/ckfinder/userfiles/files/18683825044.pdf
    • https://www.abrasco.org.br/ckfinder/userfiles/files/geguvolazewipedetosivo.pdf
    • http://3gr-group.com/ci/userfiles/files/96682341893.pdf
    • https://www.habitat-morvan.fr/ckfinder/userfiles/files/12618850021.pdf
    • https://netkat.in/ckfinder/userfiles/files/84471421675.pdf
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/f4mkqa77f800shh6v0c7npfnnh/38604273853.pdf
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/16136d728a923e---futudufap.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=efectum+app+download+without+watermark
    • 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_off0000c576.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC576 16792 bytes
font_01_sfnt_off0000dd8d.bin
9c9b1f5a1fbf8635ea042535807ee2d6fa1c7784d3dffdc5d15e22257317a871
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD8D 10980 bytes
font_02_sfnt_off0000f6d1.bin
098bb5a1005b1c1458af63e82c68c4818f68086e4e48f0b314f41cc071881076
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6D1 17348 bytes