Malicious PDF — malware analysis report

Static analysis result for SHA-256 8032de0b071374a8…

MALICIOUS

PDF

69.3 KB Created: 2021-10-01 02:57:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: a6796fc2d83bc90d6abd61e8284f0690 SHA-1: c5c4ab80be04d18181c04a1d42e5e142569a6bdb SHA-256: 8032de0b071374a8592fadadcb388c9c3e655732eac20d14bb42b8708f27c5b7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many of which point to compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using such documents to create a link farm, likely to improve search engine rankings for malicious sites or to host phishing content. The ML classifier and ClamAV detection strongly suggest malicious intent, with the embedded JavaScript potentially being used to redirect users or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • 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.
  • 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 https://demoepaper.104portal.com/upload/serback/files/20210929011751.pdf In PDF document text
    • https://www.marjojaspers.nl/ckfinder/userfiles/files/vajizakikigokusolufejova.pdfIn PDF document text
    • http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/18955575958.pdfIn PDF document text
    • http://short-story.ru/upload/file/9063553741.pdfIn PDF document text
    • https://www.jancsoalapitvany.hu/ckfinder/userfiles/files/vutivujalozofoxogoxada.pdfIn PDF document text
    • http://ueros.fr/admin/ckfinder/userfiles/files/89344557949.pdfIn PDF document text
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/2ukqnqlgiin373t2k2dak3b24j/53091942350.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fa6892408d---kiranirejolotizopu.pdfIn PDF document text
    • https://kitapkapla.com/upload/ckfinder/files/tiworarupewevavunudepuv.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/f4vekfnphsig5v6uu3hooc42n5/bazebibo.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/c0lmlahtudaqmgdgjntbrt1548/10821955579.pdfIn PDF document text
    • http://gccde.com/downloads/blog/geust/files/28881441742.pdfIn PDF document text
    • http://3e3i.com/UserFiles/file///50634700470.pdfIn PDF document text
    • https://bravo-hk.com/userfiles/file/405341966.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/161370fadad175---zigofikeladobege.pdfIn PDF document text
    • http://nanchang.chinatupai.com/web/js/ckfinder/userfiles/files/wemikefitapividoto.pdfIn PDF document text
    • http://merwepizza.com/upload/file/jevoba.pdfIn PDF document text
    • https://jeneifogaszat.hu/cikkdata/files/gapubefiwuvufomakoxe.pdfIn PDF document text
    • http://ozhelalikram.de/resimler/files/tavipifuve.pdfIn PDF document text
    • https://mcq-exambd.com/app/webroot/ckfinder/userfiles/files/lonelubuxigezamiginawes.pdfIn PDF document text
    • http://balalajka.nu/media/61786494728.pdfIn PDF document text
    • http://miyagi.chi-kara.net/Upload/files/45874408325.pdfIn PDF document text
    • https://kocgrafikavukatwebsitesi.demowebsiteleri.com/upload/files/68449083208.pdfIn PDF document text
    • https://lenaoyunlar.net/calisma2/files/uploads/newasoxerowib.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=how+to+enable+otg+on+androidPDF link annotation
    • https://bep.semmelweis.hu/userfiles/file/47442609789.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_off0000b14b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB14B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c962.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC962 10472 bytes
SHA-256: 0df30692b3f7de1b8918eb2fcbad27b316954958c91de003fb9c832ea1041bae
font_02_sfnt_off0000e10d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE10D 15356 bytes
SHA-256: 1da5083f8fd4dd0fa7ba5b1d0eca0d1059fa39fc834d75fe2111002cf8c60781