Malicious PDF — malware analysis report

Static analysis result for SHA-256 b21507791f5cb6e4…

MALICIOUS

PDF

78.9 KB Created: 2021-09-15 14:55:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2d8cbe82bfcab857419ff21c27b454d7 SHA-1: f7165b6589426fc7830fc1237fd948b80884293a SHA-256: b21507791f5cb6e42cc630cfb7e392a718b69febe995c924620d9256081ebdc1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to lure victims. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of embedded JavaScript (T1059.007) suggests potential for further malicious actions beyond simple redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://dolphinegypt.net/userfiles/file/talepak.pdf In PDF document text
    • http://autosoftware.company/autoresponders_images/files/jepanazapabixala.pdfIn PDF document text
    • http://cerritos.songhakbbq.com/uploads/files/nasetenuxi.pdfIn PDF document text
    • https://postelezmasivu-olomouc.cz/ckfinder/userfiles/files/29003046051.pdfIn PDF document text
    • http://jamurgoreng.net/contents/files/galijigalixuxo.pdfIn PDF document text
    • http://sineadstone.com/userfiles/file/22526366956.pdfIn PDF document text
    • https://riosemarescentrodemergulho.com/ckfinder/files/20314485019.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/6t7l26hb22v40ctskd449eljg8/jalesatotokutagibojamid.pdfIn PDF document text
    • https://www.tamilsaga.com/ckfinder/userfiles/files/70609508629.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/161379c9fe5fb8---64298538763.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16137d7f20c178---jovazigumedopafivawuzom.pdfIn PDF document text
    • https://medgal.pl/admin/ckfinder/userfiles/files/63978655758.pdfIn PDF document text
    • http://sreema.org/FCKeditor/file/41041993533.pdfIn PDF document text
    • http://24x7taazasamachar.com/assets/ckfinder/core/connector/php/uploads/files/3605964513.pdfIn PDF document text
    • http://origo.ws/userfiles/file/lajivumofuzikinurubitif.pdfIn PDF document text
    • http://niengrangchuyensau.com/upload/contentFile/file/50587396138.pdfIn PDF document text
    • https://safetypadlocks.eu/eurostyl/photos/file/60944527883.pdfIn PDF document text
    • http://liga-stf.ru/i/upload/files/kepogokasidibogufi.pdfIn PDF document text
    • https://photopoligrafic.ru/ckfinder/userfiles/files/kotizapesuzovosaxe.pdfIn PDF document text
    • https://privatecambodiatour.com/userfiles/file/4250118973.pdfIn PDF document text
    • https://jlgardner.org/home/jlg/public_html/ckfinder/userfiles/files/9721709021.pdfIn PDF document text
    • http://xn--2o2b17g32e8xisqq.com/userData/board/file/58135793994.pdfIn PDF document text
    • https://imad0c0.com/js/ckfinder/userfiles/files/1976589210.pdfIn PDF document text
    • http://testplanet.nl/uploads/files/noseguxa.pdfIn PDF document text
    • http://masan315.net/board/imagefile/file/poxexogodinagaxevi.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161410df209ab2---sisumuxexipigeditaxe.pdfIn PDF document text
    • https://lesartsdansmonjardin.com/userfiles/file/20210913171645.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=baixar+media+player+classic+para+androidPDF 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_off0000ce9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE9B 17888 bytes
SHA-256: 997e060dcd3633c8f6becdefe3c80c0a4273cdc7650da27a654f4baefc5ae0e8
font_01_sfnt_off0000fc64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC64 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001147b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1147B 10844 bytes
SHA-256: 4aec6060471e037f93a2ed1664d8691f43557c71b7e6dd4253aae7562f559742