Malicious PDF — malware analysis report

Static analysis result for SHA-256 83f509c00d358083…

MALICIOUS

PDF

78.6 KB Created: 2021-09-03 17:14:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ab54f2902c393a407ab8f4c749b8f329 SHA-1: 580988c54b8e27b9c97bf9bac9656c7e752ccc74 SHA-256: 83f509c00d358083f25382ec5179d9fb87d70c6c47de76d46a64e920647254a2
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to compromised websites and disposable hosting, suggesting a phishing or malware distribution scheme. The PDF structure and embedded links are indicative of a link farm attack, aiming to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://eslms.com/userfiles/file/mirodoluxadapek.pdf In PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606edae56f690---foguvobasuzokuvuner.pdfIn PDF document text
    • http://alemotta.com/resources/original/file/58735533694.pdfIn PDF document text
    • http://mini-garden.ru/userfiles/file/nibawupafadiw.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/4601cf9480bbe3da95871219288fb933/zusapuwukonipezexuvo.pdfIn PDF document text
    • http://innotec-industrie.be/userfiles/file/39065631621.pdfIn PDF document text
    • https://corianderedmonton.com/ckfinder/userfiles/files/zalukipewa.pdfIn PDF document text
    • https://callmarkinvestments.com/callmark/files/10893350361.pdfIn PDF document text
    • http://zonwering-nederland.com/ckfinder/userfiles/files/xexozake.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160a157a94e42c---takaza.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/3baffc3c6b8601a6324c1c55ef386acb/jaregujatisuzovurojup.pdfIn PDF document text
    • http://baovethanglongmb.com/upload/files/nekipa.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/57465171655.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/161240486b8e10---ropawawaf.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/4683ea01ba16ee6066f54a3130975553/bifalis.pdfIn PDF document text
    • http://ingfrimale.com/userfiles/files/pijuwulinujemubodiba.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/5c17c2c6afd4b40d87c3de29767f9253/45641641414.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/18637696082.pdfIn PDF document text
    • https://pracowniatechart.pl/fckpliki/file/6068229595.pdfIn PDF document text
    • http://stellar-toys.com/ckfinder/userfiles/files/12242606193.pdfIn PDF document text
    • https://muachungbaohiem.com/uploads/userfiles/file/54649227541.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/96041291007.pdfIn PDF document text
    • http://gamebonda.com/ckupload/files/bovulijezovovize.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=catalogo+mitutoyo+pdf+italianoPDF 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_off0000cb20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB20 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e337.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE337 10688 bytes
SHA-256: cf132c39f44b3d19db590e8e32616adc59aec8a2a6bd5968a700857356cc0c05
font_02_sfnt_off0000fb84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB84 19084 bytes
SHA-256: f63d5cabb6bc8ac9dae4b579941be5baaaf36f89d9118ced016982c00de93db6