Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8f3611edd6923e0…

MALICIOUS

PDF

85.7 KB Created: 2021-06-26 03:09:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 45585a0b98a2b0ecce89f0dd7bfb04b4 SHA-1: 25270b9eb79b53e45932ab9a688d6986f53a597e SHA-256: b8f3611edd6923e0f894c750088dfcad1ad20a8516c30c2188a5ff5fbac5cfc4
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or SEO poisoning campaign. The embedded URLs, while some are marked benign, are part of a larger pattern of redirecting users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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.greenbriarpropmgmt.com/wp-content/plugins/super-forms/uploads/php/files/019036a1e922e36e70347e4d3788d7aa/rarikofufijuk.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bad2b8ac2b---41017017473.pdf
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/0d5bcb623118664dcef10cb46e45ae3c/5853257289.pdf
    • https://vipbeachhouse.com/uploads/editor/file/majuzefubebu.pdf
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/dlnmn5c3nlnomegf65lenk4pf1/48732939333.pdf
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c9b4702da4b---renefagej.pdf
    • https://yuss.it/file/1264502855.pdf
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076da2345c6d---95436564362.pdf
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/1f5c728d8a4d5d35a56d2ea969693788/kuvebewizamegijeganabazeb.pdf
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/d57d44c0f1b9e1fc173e739a114aa5df/tuxabonaja.pdf
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16071447f6d05e---34658898697.pdf
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/0q6mq12jhr0ju6ghlfbsd0ge05/xebumonatefelitafadulejo.pdf
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/45v7irv7vn88pk8n39ggck6scr/kurikukipoketijuda.pdf
    • https://mn-lawfirm.com/box/userfiles/file/85748694243.pdf
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/2016babffd325649edf332cb7a3643ba/62915451852.pdf
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/930b8c133b2ef727413eca7f018c5fbd/fekulojusenitawunifosulod.pdf
    • http://heibldr.hu/FCKfeltoltott/file/60639170222.pdf
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c33c01d96cd---lapevejema.pdf
    • https://casabresciani.it/uploads/file/1494235512.pdf
    • http://ciskmv.com/css/file/31686348184.pdf
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607831e0970a5---zevetanakiden.pdf
    • http://assistance.uz/images/shared/file/xuropazitunilunibadus.pdf
    • http://fly.no1-yes.com/userfiles/file/29796827483.pdf
    • http://jatyn.cn/upfiles/202105/file/1621194665.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=queen+and+slim+watch+free
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea55.bin
4115ba9aba12ac18cf12af8f7403a99d3ecb9edbdf08c3d79c1b589c42494b2f
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA55 17144 bytes
font_01_sfnt_off000116fd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x116FD 16792 bytes
font_02_sfnt_off00012f14.bin
26bf62c6ed882b41a931eae0956dbfefc5858dea9e2fa84f4a879dc3dce1e128
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F14 10868 bytes