Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f4330260d435b94…

MALICIOUS

PDF

82.7 KB Created: 2021-08-10 02:41:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: bdc102a074164533c1fb8842b5dacdf4 SHA-1: 5efca6e89309386ba3723cf76cd6805cfb459651 SHA-256: 4f4330260d435b9432643c4dea34104d18b11821d24c63bad1193e906135bf9d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a link farm with numerous URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or SEO manipulation. No scripts were extracted, and the document body was unreadable, but the heuristic firings clearly point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://soupworld.de/upload/file/3112836320.pdf In PDF document text
    • http://austria-ex.com/images/blog//file/loberovar.pdfIn PDF document text
    • https://kawanmto.com/contents//files/21294207292.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/28423992757.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bd8f854a98---geguzibi.pdfIn PDF document text
    • http://funperm.ru/content/file/wajosonuwaxikagejupe.pdfIn PDF document text
    • https://carea2plus.com/wp-content/plugins/super-forms/uploads/php/files/63f39bf37d7185c344261421208b7802/83873658243.pdfIn PDF document text
    • http://kamennykoberec.eu/editor_uploads/system/files/wuvifijomo.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/94946639201.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/c522357b5062f71e8600f5f384d5e07d/46390243607.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/762f4d348f440a311ba0a5da4c239817/gegatotagizi.pdfIn PDF document text
    • http://dunajecbiala.pl/upload/File/95791359945.pdfIn PDF document text
    • http://pinturasoltra.com/images/slider/files/katapojozadijetifavige.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/723j8nlivjh9jtggq7c8fs63bs/vizomapiwafuk.pdfIn PDF document text
    • https://nwdglobal.com/ckfinder/userfiles/files/loduvodoxujidewewagibapi.pdfIn PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/24085355396.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/zuvinozugexul.pdfIn PDF document text
    • http://tieclangman.com/Images_upload/files/4243980256.pdfIn PDF document text
    • https://ideylia.fr/uploads/file/13107870189.pdfIn PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/xilarun.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160968c479ade2---69518397351.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16108129606fa7---majosotoredufoxavipime.pdfIn PDF document text
    • http://westpakusa.com/phpsites/vertical_living/uploads/file/72800565300.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e3c71b7b9ad---90802695440.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=solve+quadratic+equation+by+factoring+maze+level+1+answersPDF 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_off0000db6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB6A 11656 bytes
SHA-256: 5d156b73c5b4870a5a76ec444a8ee5511c5ca6a02947124c6e334599c76d2463
font_01_sfnt_off0000f6cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6CB 17088 bytes
SHA-256: d014e788f39aee14bb5647aa06cad436e46517fb1b018e466a318c4960a81235
font_02_sfnt_off00012360.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12360 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1