Malicious PDF — malware analysis report

Static analysis result for SHA-256 3273a4ecd7b12af0…

MALICIOUS

PDF

76.1 KB Created: 2021-09-12 07:43:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6a7f8a29b431172a837eb5673c0643b9 SHA-1: f7d6a90546731847a89b4b41316bdd8219eb6da3 SHA-256: 3273a4ecd7b12af0eddf6371af591775a20f85bbb111f3b14fa3fc9ead07da88
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it functions as a link farm. Several URLs point to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute or host malicious content. The presence of numerous links, including one with UTM parameters, indicates a potential SEO poisoning or phishing lure.

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://www.gryf-wet.pl/ckfinder/userfiles/files/kefakuloguwosukitam.pdf In PDF document text
    • http://planbmedia.hu/files/46336962718.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1612f3d75d0668---tovawuneg.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/78jbrdosl2as8k2osal434flg1/60197992678.pdfIn PDF document text
    • http://skkl.cn/filespath/files/20210911151225.pdfIn PDF document text
    • https://hssanesteban.cl/files/83518381165.pdfIn PDF document text
    • https://sharenkon.com/files/vosajomeweva.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/vusuvetusubo.pdfIn PDF document text
    • http://tipsclubcr.com/campannas/file/tuwuzazewalalujulufu.pdfIn PDF document text
    • http://podwierzba.eu/ckfinder/userfiles/files/bizafuzaxavuwiziguk.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/s6jksr3hlphd3sb2l25ehldvl3/70035129600.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/12cb6c6fcc248424c74d1cf4e271351a/nirabudusetuvuw.pdfIn PDF document text
    • http://kanchanaspa.com/ckfinder/userfiles/files/52573578142.pdfIn PDF document text
    • https://hr-serdahel.hu/images/file/xavozenezitifuxupoxopepof.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613adf371245c---jamisoguwol.pdfIn PDF document text
    • http://exima.kr/userData/board/file/24201009725.pdfIn PDF document text
    • http://idcla.net/upload/files/12915168621.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/momifudejuratesu.pdfIn PDF document text
    • https://larustt.com/upload/ckfinder/files/4669554620.pdfIn PDF document text
    • https://foodexgida.com/uploads/files/71210170597.pdfIn PDF document text
    • http://eggtesting.com/admin/uploads/file/jopiwikot.pdfIn PDF document text
    • http://flashdisplay.net/UploadFiles/FCKeditor/20210907225515.pdfIn PDF document text
    • http://usefchina.com/uploadfile/file///2021091212082035.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=free+maxx+free+dj+alok+diamonds+%26+elite+passPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bfe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFE0 19272 bytes
SHA-256: 67558853194d20e7f78589f9e8883379faab582d4606c85d5a64abdffb0bfe4e
font_01_sfnt_off0000f1fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A13 10716 bytes
SHA-256: 443c3ee22298c12b941573058dda9561fb0e24cd1649e6f3660090c417fd814b