Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ce8ad84e6e64db1…

MALICIOUS

PDF

71.8 KB Created: 2021-09-09 23:14:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 29f516d7729d996b6600417d2acab60c SHA-1: b580062c2f3b1522c0b1ff32d0211dd5721a8b65 SHA-256: 4ce8ad84e6e64db1e1ab9d02ddcac76d670e3073847bccf55c08b4b5e2f103ba
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF acts as a link farm, directing users to multiple external URLs, some hosted on compromised WordPress sites. While no scripts were explicitly extracted, the PDF structure and link farm behavior suggest it's designed to redirect users to potentially malicious content or phishing pages.

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 http://xn--vb0b83rba554gca.kr/page_data/file/20210903113715.pdf
    • https://kaowei.tw/image/files/20210905_114216.pdf
    • https://mttrasportisrl.it/dati/upload/file/venebezobinofamawepuj.pdf
    • https://v-rshine.com/upload/images/files/76875598126.pdf
    • http://zzquansu.cn/d/files/dogejejapagoxejijew.pdf
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/4f477c5c6030659a1a73481587b56115/zedamivosiba.pdf
    • http://tobn56.com/UpFiles/file/75291644137.pdf
    • https://www.tzounakos-insurance.gr/ckfinder/userfiles/files/29352224412.pdf
    • http://prompol.com/media/file/72616303682.pdf
    • https://taechoclub.com/FileData/ckfinder/files/20210904_958837A4C5B8EBAA.pdf
    • http://eis-pieschel.de/UserFiles/File/migafolenemixovu.pdf
    • http://purepassion.pl/userfiles/file/64129486470.pdf
    • http://chinazzjx.com/d/files/81004426827.pdf
    • http://poslovniimenik.net/firme_data/files/30109859631.pdf
    • http://3sdent.com/upload/files/46226299023.pdf
    • https://hydratrend.com/application/third_party/ckfinder/userfiles/files/43288670415.pdf
    • https://tranduongauto.com/app/webroot/files/images/pages/files/63436135082.pdf
    • http://netmutum.com/userfiles/file/resozikujavetu.pdf
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/161306932954f9---jelefosejotakesizivof.pdf
    • https://ikincielinmak.com/upload/ckfinder/files/pakugamew.pdf
    • http://ipayon.com/root/FCKeditor/file/befugemubazemiwaw.pdf
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/161302ea8ee9c9---86407414324.pdf
    • https://eletvital.hu/uploads/files/sutoveborije.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=past+simple+exercises
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b867.bin
9cd16e755d1c183372a09922cd5978b8432285a92dd915af74d138ef7d2bb693
pdf-font-stream PDF embedded font (sfnt) at offset 0xB867 10416 bytes
font_01_sfnt_off0000d007.bin
0bd509b603c72a419a40028e88fc54242649a4f1fc1de690747ef46435e03db3
pdf-font-stream PDF embedded font (sfnt) at offset 0xD007 16376 bytes
font_02_sfnt_off0000f9c4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C4 16792 bytes