Malicious PDF — malware analysis report

Static analysis result for SHA-256 b743af252de272b0…

MALICIOUS

PDF

78.4 KB Created: 2021-09-17 09:09:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8f8dfd697bd23bfaa644b0cab51e1b26 SHA-1: abb7d35a7e97abdaf4b250b6c32263b997db6e29 SHA-256: b743af252de272b0c7f3418f2f927e6e92e1fedc50956fde5141b4fd79c9a334
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of multiple external URI heuristics and link farm indicators reinforces this assessment.

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 https://catamma.ru/uplcv?utm_term=csr+racing+2+mod+ios+no+jailbreak PDF link annotation
    • https://groupunsur4.com/contents/files/zepitijobotebizo.pdfIn PDF document text
    • https://dazhonghua1688.com/ckfinder/userfiles/files/914907555.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/16135f62486bfa---wixapikubutixepurap.pdfIn PDF document text
    • http://japanbizkorea.com/userData/ebizro_board/file/zosudibowamapaxi.pdfIn PDF document text
    • http://fabtur.ru/upload/files/58833303496.pdfIn PDF document text
    • http://jrecchina.com/ckeditor/ckfinder/userfiles/files/dozokesofunonenabuteremi.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/4418479267d84afcfadf7989656fd35e/27497132825.pdfIn PDF document text
    • http://aajude.pt/backoffice/ckfinder/userfiles/files/61633302156.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/gasajixagepijazav.pdfIn PDF document text
    • http://texmet.pl/userimages/file/tekatitaxokes.pdfIn PDF document text
    • http://vin-baietii.ro/ckfinder/userfiles/files/33844541088.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161316071c072d---pikiwu.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/0of15i0cqqnqe0rh22ga5r3cvc/mufubopusixunobifafoput.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/retisuxizavemolixo.pdfIn PDF document text
    • http://obraz-tlt.ru/userfiles/file/piluledu.pdfIn PDF document text
    • http://grasslandtj.com/upload/files/31341824519.pdfIn PDF document text
    • https://thai-airpark.com/ckfinder/userfiles/files/dexuvifuxaze.pdfIn PDF document text
    • https://pelicanfinancialnetwork.net/ckfinder/userfiles/files/11874234325.pdfIn PDF document text
    • http://dasbluemchen.com/98672598429.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/85676989075.pdfIn PDF document text
    • http://quesnelbusinessnetwork.ca/userfiles/file/30812907669.pdfIn PDF document text
    • http://jonme.net/ckupload/files/7465659287.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/disoka.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_off0000ca03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA03 11128 bytes
SHA-256: 776530c12c0e05b5b502a30295af560bd103afeb492494537c8174902f9e96c4
font_01_sfnt_off0000e3bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3BF 18300 bytes
SHA-256: ea8330641e930384b12a7185a1482078f4ec7c119cf5ad955289eb65e4707e13
font_02_sfnt_off000113b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1