Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a4039d9d1cf7cc9…

MALICIOUS

PDF

81.8 KB Created: 2021-09-06 10:12:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 885e60c115c310036b4ed5687dbd18ee SHA-1: 7f7ec2964057ea55064ceddbf759f0203ce0a09d SHA-256: 1a4039d9d1cf7cc91969c343b60b798fb1b3a187274c7e19058eb096f4dd5afe
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. The PDF contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting it functions as a link farm. This pattern is often used to distribute phishing content or manipulate search engine rankings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://zimmerei-possert.at/65095129128.pdf In PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/161219dfbe7de5---dawiwaxuv.pdfIn PDF document text
    • https://maintogelonline.info/contents//files/62162855782.pdfIn PDF document text
    • http://foxhill101.com/userimages/68633834758.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/pj5ismqv2kbu3mf7225uo17pk3/54311853420.pdfIn PDF document text
    • http://18554080.com/userfiles/file/59221837480.pdfIn PDF document text
    • https://bibliotheque-des-arts.com/ckfinder/userfiles/files/rudidazubutir.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b1420b39d3---83348511382.pdfIn PDF document text
    • https://cornerstonelaw.eu/userfiles//file/351319007.pdfIn PDF document text
    • http://www.klimavill.com//data/editorfile/novanekipusajazobu.pdfIn PDF document text
    • http://norilskgu.ru/userfiles/file/jefitonufudum.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a78ae7ca01b---29326867977.pdfIn PDF document text
    • http://chobacgiang.net/webroot/img/files/89060080149.pdfIn PDF document text
    • https://sasalidayanisma.org/uploads/file/pesalabonenelog.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160bd432f5a9bd---51690652808.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/1607819db88c6c---tilak.pdfIn PDF document text
    • https://cosplay-expo.it/ckfinder/userfiles/files/76073892397.pdfIn PDF document text
    • https://egyiksem.hu/uploads/file/38474495369.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/98df1a2c83f3c1cb776ae6c3edc71204/jedorujewiwatasemonu.pdfIn PDF document text
    • https://aymexco.ro/ckfinder/userfiles/files/20720288112.pdfIn PDF document text
    • http://cjcounsel.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/28675296924.pdfIn PDF document text
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/jonamakerazedujumefeta.pdfIn PDF document text
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/a16facde00d8a34ccad88c282acc3692/42614727553.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/7c38129e03fcc81d5a7fa17c727e0af5/dobowiro.pdfIn PDF document text
    • http://doubles301.jp/files/ckeditor/files/zavaxuvu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=electrolux+washing+machine+manual+eww12742PDF 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_off0000d9fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9FA 17424 bytes
SHA-256: e91eb77f418005034c9ff1cdfc243098221cb5f9d76fbee02397b7b3497809e4
font_01_sfnt_off000106d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011eee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EEE 11248 bytes
SHA-256: 6a885eb41dde53f95059623cf3e80e56b01f28b0ebe962bb45f1e466bbdea828