Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c79cca291f335db…

MALICIOUS

PDF

73.9 KB Created: 2021-08-31 00:08:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: f1c08ccc2c1e9c4a0385406dd38951af SHA-1: 65b56f1be2d9908f73f305552ed4632d47afe2c4 SHA-256: 4c79cca291f335dbb71382c105fe7fd080f2631c67e2924165ce3c0e1bae8051
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous external URIs and links to compromised WordPress upload storage, suggesting it functions as a link farm to distribute malicious content or phish for credentials. The PDF structure and embedded links are consistent with a spearphishing attachment delivery method.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://wastran.ru/uplcv?utm_term=slope+practice+problems+with+answers PDF link annotation
    • http://www.alexgis.com/siteuploads/editorimg/file/73369091057.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ad36d208da---63975671808.pdfIn PDF document text
    • http://romanakladatelstvi.cz/userfiles/file/26747225710.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/bdlsr7qc0j0u55is1ab00i9sck/47384608349.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/646f3245f69e4d086d23f06dd33849e4/56026513959.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210726232325938.pdfIn PDF document text
    • http://wecans.net/_UploadFile/Images/file/puvijavomulezev.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160b5a81e0a31b---26178111701.pdfIn PDF document text
    • http://wixoon.hu/upload/file/botapanesezow.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093fb653aca4---jemujalofubenobegane.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160841976c6966---xaxikulumapikonu.pdfIn PDF document text
    • http://kielcenoca.pl/files/file/wiruvivujufabawutafuz.pdfIn PDF document text
    • http://agiteam.org/clients/b/b0/b0c4817036ef1cb73596cc935f3fa86d/File/83264952642.pdfIn PDF document text
    • http://kingsfinancialconsulting.com/userfiles/file/zululusorobenoxusinen.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160edc75f071b7---puxigef.pdfIn PDF document text
    • http://larrysiegellaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kunaremeperepisubupu.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f252cca226---wotajusuvebokakuno.pdfIn PDF document text
    • https://eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/83233957226.pdfIn PDF document text
    • https://truckforceone.eu/upload/editor/file/26327410455.pdfIn PDF document text
    • http://arohitourandtravels.com/userfiles/file/jovegemadu.pdfIn PDF document text
    • https://biocenfis.es/uploads/assets/file/40308743958.pdfIn PDF document text
    • http://cinebuzz.be/uploads/userfiles/files/wepamovolenozafivuxam.pdfIn PDF document text
    • https://girilawfirm.com/content_files/files/foraji.pdfIn PDF document text
    • 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_off0000bd56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD56 10940 bytes
SHA-256: 9143e2023013a355ffca9a0b34d25a674d5f93b713851539b1514147a9040965
font_01_sfnt_off0000d655.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD655 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE67 17164 bytes
SHA-256: 9b308a25c0df05d26d33eedb6ebd883f944235cf061200761ce0edfc29e510a5