Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f932eab1092f6f6…

MALICIOUS

PDF

82.0 KB Created: 2021-09-04 15:22:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 8c66338f9be769b847420cca105d683c SHA-1: ab527b59a05e0313f19152df2bc3ab52a2d32ca4 SHA-256: 4f932eab1092f6f654a16a15ffd0bc9f10c27c51e319a65c5ab3f3e29104213f
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress upload directories or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://hum-lucknow.org/test/fckeditor/file/58015583712.pdf In PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/39b3764691d92ae5d3ced0d775f5a406/37332887888.pdfIn PDF document text
    • http://naturallabs.de/userfiles/file/dezirov.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160faeab65eb3d---rorabetufovupakabu.pdfIn PDF document text
    • http://irina-beha.com/ckfinder/userfiles/files/51289549724.pdfIn PDF document text
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/31520730395.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/e0c8e4bdfd540b128863488a5cb5b1a2/54757463183.pdfIn PDF document text
    • http://yjsyrj.com/userfiles/file/8347120165.pdfIn PDF document text
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/9qoh7k9oljktqpki3oqp0p7l5e/65530069581.pdfIn PDF document text
    • http://bjyhyy.cn/filespath/files/20210830000606.pdfIn PDF document text
    • http://guojingmall.com/userfiles/file///wezufawadizugaloxed.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/160ad09a6c6206---8840171511.pdfIn PDF document text
    • http://intersonik.eu/upload/files/76945283038.pdfIn PDF document text
    • http://gustosandvic.com/ckfinder/userfiles/files/72035788220.pdfIn PDF document text
    • https://adsbudget.net/userfiles/file/tetuluvazafoxuzafegezilik.pdfIn PDF document text
    • https://drisraadentalcenter.com/userfiles/file/57588574410.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076ae04ea079---ditazemituriwabetakebewu.pdfIn PDF document text
    • https://gangnampools.com/contents//files/fepixu.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161092b6e1cab5---6896777619.pdfIn PDF document text
    • http://studiozoppini.com/userfiles/files/piluzapavidepetunex.pdfIn PDF document text
    • http://gospel-pour-100-voix.com/fichiers/newsletter/file/gowipiwubinebekizuka.pdfIn PDF document text
    • http://likebarcode.com/image/files/20210814_172139.pdfIn PDF document text
    • https://miet.hu/kepek/78322714266.pdfIn PDF document text
    • http://chongthamnguoc.vn/img/files/bulamazemeninaxitemamos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=pythagorean+worksheet+with+answers+pdfPDF 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_off0000d99a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD99A 11024 bytes
SHA-256: 4b344023ef35ef67d51bdd6130433720b4bed520afc8fc0435eb1e496f4e178a
font_01_sfnt_off0000f318.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF318 18180 bytes
SHA-256: 700da461a9450fca605d0ed8187ab4fd53eaa6c7d6075b46a2e1ac2f403915ab
font_02_sfnt_off0001225b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1225B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1