Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fbf51c9ba27b87f…

MALICIOUS

PDF

96.7 KB Created: 2021-08-13 18:54:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a85bc80de64ee764286f9aea4db1779b SHA-1: 2a59aeec61e6e66a6ea18b6f8ac81bdf06ee589f SHA-256: 4fbf51c9ba27b87f79b6203a2d5efd89d23bee75aec38943172ba958bbbaf8de
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It contains a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting an attempt to distribute malicious content or phish users. Although no scripts were explicitly extracted, the PDF structure and embedded URLs indicate a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9920

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://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/72shu4ghqg61e13ip2il7hh4j3/vawifajibuti.pdf
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16084476a9c490---jitoxukamizixusedizafo.pdf
    • http://iviltra.lt/images/files/19146047547.pdf
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608005adb4e62---lutoxalodigozumuriruku.pdf
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609f7d56941ae---xumazimavadamavixoloje.pdf
    • http://macro-e.com/app/webroot/userfiles/files/zixisujixopubiritu.pdf
    • http://olympicburger1988.com/uploads/files/fevigi.pdf
    • http://szilasfood.hu/pic_upload/files/mebokusojupevupetajapoba.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608d73c3887ba---namojuzojolaz.pdf
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609c4ffdb094b---lokukutadodogedula.pdf
    • http://thaoduocvn.com/userfiles/image/file/xulaxutaxolusinow.pdf
    • http://neodermclinic.com/file_media/file_image/file/58364132472.pdf
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607e50949d41a---xobexezutelofiru.pdf
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/160982a80a685a---rebejuvamerejib.pdf
    • http://studioaba.net/userfiles/files/tadedenirajavisuxudodot.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160725c26a84bd---rarisijitowumelewerox.pdf
    • http://aarogyamedico.com/userfiles/file/piveputugevigedupejolu.pdf
    • https://www.indoorclub-informa.com/boletines/img/file/28601935939.pdf
    • https://karapinarinsaat.net/userfiles/upload/file/42632485056.pdf
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/qidmvf3jnjl8ugrhidfibf5ib2/didosejagof.pdf
    • http://angelofthewinds.net/ckfinder/userfiles/files/mosox.pdf
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/7d3619cd0b3c0557fdc9213b14caf6af/89431774673.pdf
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b295c19597f---75108249610.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=relion+premier+compact+review
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000faed.bin
1eb09c0fec2e2239353c654ec9c6abe65e8268ec8ddafca8349449574125e1bb
pdf-font-stream PDF embedded font (sfnt) at offset 0xFAED 19160 bytes
font_01_sfnt_off00012d34.bin
f13f89c7c07e613e47bf428e48b95a6818c6d2ee17be040e6f7f4b749d25c260
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D34 10564 bytes
font_02_sfnt_off0001454c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1454C 16792 bytes
font_03_sfnt_off00015d5d.bin
7d15b2d6d265aaca51dda18faee70a1b8fa9d95ed54cb111fb0895789092f9ae
pdf-font-stream PDF embedded font (sfnt) at offset 0x15D5D 16312 bytes