Malicious PDF — malware analysis report

Static analysis result for SHA-256 ba5484732221d666…

MALICIOUS

PDF

71.3 KB Created: 2021-09-19 12:31:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: eb2b0ef78039d51f248997a8ab660a8c SHA-1: 87e2ee6a2ce4e31e2ebefafcb10c62519a6d3552 SHA-256: ba5484732221d6663e39a0e9c5eaaa4690c21eb78cdd3d151d4f635efc687c35
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 point to compromised websites or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and link farms points to a tactic of directing users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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://fygl.net/uploads/file/141220355158.pdf In PDF document text
    • http://aven.su/userfiles/file/94543507854.pdfIn PDF document text
    • https://al-farh-iq.com/upload/userfiles/file/22284963792.pdfIn PDF document text
    • http://flomojapan.com/upload/files/213254566.pdfIn PDF document text
    • http://akademibt.com/resimler/files/49746090423.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613fdbd2b5987---wadozowetakapozita.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161376df70a151---situvuxaxa.pdfIn PDF document text
    • http://flex-link.cn/uploadfiles/files/zagememijok.pdfIn PDF document text
    • http://color-gateway.com/userfiles/file/zikulovopobaboxipejij.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/0u7827gt01cisth8em3v8io63r/worowunoserixilunovodosun.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/nusuvij.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/6c508ca2cc63d4f3feb49dc21e5a5cae/bigudogixug.pdfIn PDF document text
    • http://lobanowscy.pl/userfiles/file/188360260.pdfIn PDF document text
    • http://gradn.ru/uploades/fckeditorfile/wivokavonidulagisi.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/gibogaregif.pdfIn PDF document text
    • http://pokwuttibut.com/file_media/file_image/file/duxef.pdfIn PDF document text
    • http://jadeite.ru/images/file/83376342149.pdfIn PDF document text
    • http://hkalc.com/userfiles/42188412703.pdfIn PDF document text
    • https://medtek.vn/storage/file/87531797940.pdfIn PDF document text
    • https://marosme.ro/hirek/file/58263753366.pdfIn PDF document text
    • https://sowlindia.com/userfiles/file/68306355854.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16131ffd8109bf---tojefirefusozibam.pdfIn PDF document text
    • https://dynasty888.com/image/files/20210904_033023.pdfIn PDF document text
    • https://warungmimpishio2.com/contents/files/kuzume.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=add+in+chrome+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_off0000b6fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6FB 10304 bytes
SHA-256: f0493d14133fc11d337dba97d31680a463c124c7d47e0d6f0b5f5ff106d84798
font_01_sfnt_off0000cded.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDED 16256 bytes
SHA-256: 46dd81e7a0e3d5ee6e7516cbb20440cf2277a57ff78539180444c59989bbb668
font_02_sfnt_off0000f778.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF778 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1