Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb810eddb12e5e81…

MALICIOUS

PDF

95.2 KB Created: 2021-08-12 04:56:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 370f35d8fad77e2ed8ed1d82f9824adb SHA-1: f06fbb095c766b899a653f188c7ad81fb9ec775d SHA-256: bb810eddb12e5e8170c8fd26f400d90e7d2c9e0b1b37ad63c92abf0f5e5fb952
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, indicative of a link farm. ClamAV and ML classifiers strongly flag this as a phishing or malicious PDF. The presence of multiple external URIs and a link farm structure suggests the primary purpose is to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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 https://equinox-e.com/upload/UserFiles/file/16491009593.pdf
    • http://coyada.com/up_images/up_images/fesukituvolilotawapu.pdf
    • http://decom.pro/admin/ckfinder/userfiles/files/26814468897.pdf
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/16087018b6ef65---77890954503.pdf
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/1606f532488cfa---62097863548.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3dc9f027dc---27105489236.pdf
    • http://ms-beauty.com/ckfinder/userfiles/files/jukuwa.pdf
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b07d68a219f---22262764586.pdf
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609835e6ca5b4---84343363835.pdf
    • https://2acontractor.it/images/file/38925704979.pdf
    • http://shukokai-voves.fr/userfiles/file/xuzakamatebewuvugivigep.pdf
    • http://zkojicin.cz/userfiles/file/kafewure.pdf
    • https://grancom.by/upload/docs/gafimaroku.pdf
    • http://schs1968.com/clients/861610/File/nesazovulunudotimasegeb.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16079bc75b485d---37808169074.pdf
    • http://boothbayharborshipyard.com/userfiles/file/mimexajuruw.pdf
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cbab923cb96---50115263364.pdf
    • https://bagstyle.uz/images/file/goruwit.pdf
    • https://selispin.com/calisma2/files/uploads/34230205364.pdf
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/gv2goa1q7t1a7m1bvv8kse1qkf/tofose.pdf
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b199f586d14---jefiwufivisufunugi.pdf
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/76284545375.pdf
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/3a55f34019aeb66eb3c0d4ad0edaadeb/nezozeteso.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=mi+primer+beso+libro+rese%C3%B1a
    • 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_off0000f580.bin
66b7945b99a9c78025a9a0ace4161995b24b08b80ea391fd428eddc3553bac27
pdf-font-stream PDF embedded font (sfnt) at offset 0xF580 16544 bytes
font_01_sfnt_off00010c44.bin
d9a53b24210017f13f14a3fd7b4fbee7be89eb301b40c2f869bca3ee19bc64f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C44 10552 bytes
font_02_sfnt_off000123fd.bin
80664986dbced6e5bdc2179749039a121829f25f7b942d44ef527d8687bb7802
pdf-font-stream PDF embedded font (sfnt) at offset 0x123FD 18588 bytes
font_03_sfnt_off000153c4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x153C4 16792 bytes