Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f5d8c85015fed16…

MALICIOUS

PDF

79.2 KB Created: 2021-09-01 03:19:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6a272e600bebab6c4052f5f75257a929 SHA-1: 94c47864186bbf73c35a03a3411ae6f0df198dc1 SHA-256: 1f5d8c85015fed16e6e7fd86768ca1eef9ee395097c574101098acb6a51b24b8
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ClamAV and an ML classifier. It functions as a link farm, with numerous embedded URLs pointing to compromised CMS upload directories. These links likely serve as lures for phishing or to distribute further malware, aligning with the 'Malicious Link' and 'Spearphishing Attachment' MITRE ATT&CK techniques.

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://thedreams.cz/files/lirojotisuda.pdf In PDF document text
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077d31e11814---wedemu.pdfIn PDF document text
    • http://ytlcases.com/userfiles/file/97425219063.pdfIn PDF document text
    • http://maxgear.cz/webpagebuilder/ckfinder/userfiles/files/sifidizemufekuw.pdfIn PDF document text
    • https://afgventuregroup.com/cfiles/file/jedudixamemimigukesax.pdfIn PDF document text
    • https://universal4shipping.net/userfiles/file/xikimuxowi.pdfIn PDF document text
    • https://www.barrau-philippe-sedeco.fr/ckfinder/userfiles/files/jazitijoser.pdfIn PDF document text
    • https://dudikom.pl/userfiles/file/zupudarupetowiniv.pdfIn PDF document text
    • http://xycrusher.com/d/files/wagazigidatatazofokavu.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7ce61c6fa3---narixapofuxukibebonov.pdfIn PDF document text
    • https://www.cascatai.com.br/ckfinder/userfiles/files/jevixaxiwipunijejo.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/gvpdpdbvi26vod3svrcap80nvl/nibedu.pdfIn PDF document text
    • http://baodieptailor.com/uploads/2021-07-13/images/files/kotamemuniwuru.pdfIn PDF document text
    • http://k-yoga.org/file_upload/spaw_upload/file/20210509221425.pdfIn PDF document text
    • http://falconartistmanagement.com/ckfinder/userfiles/files/70505083022.pdfIn PDF document text
    • http://elektrostroy.kz/ckfinder/userfiles/files/sosulubenumakerupet.pdfIn PDF document text
    • http://greatwalledmond.com/ckfinder/userfiles/files/teromofagefulewad.pdfIn PDF document text
    • http://jungvassar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jutuvidogu.pdfIn PDF document text
    • http://etoprosto.ru/ckfinder/userfiles/files/63685897389.pdfIn PDF document text
    • https://jpt.mysmartedu.com/uploadimages/files/lavopejopudego.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/be6feb79086fad29ca45a07f384e370e/31124473107.pdfIn PDF document text
    • http://jfhcoaching.com/userfiles/files/19732763275.pdfIn PDF document text
    • http://jtg-antracyt.pl/files/file/37404916734.pdfIn PDF document text
    • http://4x4autok.hu/userfiles/files/menex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=lacto+fermented+peppersPDF 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_off0000d147.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD147 10600 bytes
SHA-256: c8f511834244c61d78281150219b65ce8d93774c917329e8b433f85654143a8c
font_01_sfnt_off0000e97d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE97D 17844 bytes
SHA-256: 9591e77de38e0e95e89d828b3fd5d805395c42af4f06a383932eff09af5c8c21
font_02_sfnt_off0001174b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1174B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1