Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec236803cadfbb4a…

MALICIOUS

PDF

82.2 KB Created: 2021-09-07 19:31:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f64a4bc92f57ff538b5df47106fb42c9 SHA-1: 7ef445311de5210a181af32cfc970d51551105f6 SHA-256: ec236803cadfbb4ad87f8cff6a577f09e265f911a7d9a916f378bc7fae7325d7
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to potentially compromised websites, which is a common tactic for phishing or distributing further malware. The presence of multiple distinct hosts and the use of UTM parameters suggest an attempt to obscure the true destination and potentially leverage SEO for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160790c972cb59---63669480549.pdf In PDF document text
    • http://dongfangguohua.com/ckfinder/userfiles/files/jopejevokofudasewe.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/c78f580d048158ce90d4e78406ca5dc7/boledej.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092626031262---kelasuje.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/16098a7ec4f0e3---42211949282.pdfIn PDF document text
    • http://inwama4.vn/webroot/img/files/51180053276.pdfIn PDF document text
    • http://ktcz.eu/files/files/56832428102.pdfIn PDF document text
    • http://9meclinic.com/ckfinder/userfiles/files/74839434543.pdfIn PDF document text
    • http://pastadimatteo.com/ckfinder/userfiles/files/16077171532.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/39983331810.pdfIn PDF document text
    • https://jdsliquorlocker.com/nbloom/fckuploads/file/tikuwovarutejilavebew.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084f32278a5c---nifazinexuwifesofusuju.pdfIn PDF document text
    • http://pampa.be/uploads/userfiles/files/51564763650.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085b8552a747---wokixivirulafululoza.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/e5fb088cadc6d23f738ffc949eb48883/waxuvuma.pdfIn PDF document text
    • http://analogsys.com/uploaded/file/530120188611b5d7f2bf49.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/9ae49950f9eeaeacabce46e6eb5a6736/mefowopik.pdfIn PDF document text
    • https://almondzwealth.com/administrator/imagetemp/file/zixogulejodatudapixujax.pdfIn PDF document text
    • http://marinda.ru/pics/images/file/53730532088.pdfIn PDF document text
    • http://www.lovebliss.tw/UserFiles/files/denufokugisalewuzixi.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160915b729f970---47725087812.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/4ukpvs83nj1j2g01nerqmehkev/23543571519.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=honda+accord+2008+workshop+manualPDF 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_off0000dcfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCFC 17052 bytes
SHA-256: e79672f5b0a2c1415cd4e819c2c4b2639af1f15780ee2f70cca383363fe78bd9
font_01_sfnt_off00010918.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10918 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001212f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1212F 11176 bytes
SHA-256: a4e452774cf60a872915bab881f9f3aebeffe778d473a40d33738976102b1287