Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb51a4d5a9a0c75b…

MALICIOUS

PDF

84.2 KB Created: 2021-06-29 06:52:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4eaeb568ba134a6396ad1650222c1bc0 SHA-1: eb700cd54b0c3c27c2319f46a25a2ec884fcdb5b SHA-256: bb51a4d5a9a0c75b68dc6ec22472271214bdd4f9f8168d4361d89b2ba6ef51e0
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous URLs pointing to compromised WordPress upload directories and other disposable hosting, likely to distribute further malware or phish for credentials. The document body was unreadable, but the heuristics strongly suggest a malicious intent to redirect users to external, untrusted sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/26356959442.pdf
    • http://allaboutdowney.com/userimages/75888423455.pdf
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/oqfumtp6hi2ln595q0d091clf8/xofexuw.pdf
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab518a871a9---43381694686.pdf
    • http://wonikqnc.com/upload/editor/file/1622793621.pdf
    • https://aduanaldelvalle.mx/userfiles/file/nanikokodunogatetusulu.pdf
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/c0345ee4f139df0e06dbd84d8befec87/lotizogenetuvumepuziw.pdf
    • http://ahsaipu.com/v15/Upload/file/2021551845304198.pdf
    • https://mmszke.hu/files/file/mekogatorenupupagupefamab.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16082eedaa1c0e---48214032995.pdf
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608655b85fe5a---72927099566.pdf
    • https://poolpoint.be/uploads/file/91887794785.pdf
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160ad932247a4e---42068609227.pdf
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bcb7ff60868---63446591832.pdf
    • http://acril.ru/ufiles/files/74200268649.pdf
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160bae4684cf02---ziminegovorasegaviw.pdf
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/160bfa2cce699c---koxavirawiriferexezi.pdf
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acab463bf25---dipivexanapodolu.pdf
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0098203c7d---49989167029.pdf
    • http://artside.org/data/temp/file/dugunovumetuzugepari.pdf
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607db82338540---fetivugog.pdf
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/0b322a0ff56d6ad4f97dd8044cfe1880/58455518888.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=meaning+of+the+word+addendum
    • 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_off0000e79d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE79D 16792 bytes
font_01_sfnt_off0000ffb4.bin
18af2a3bf957ad03de9da22fa273fe8dc61c93d6939e986401b22d95577be6d9
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFB4 10764 bytes
font_02_sfnt_off00011818.bin
385824390b8b62c6cc37c4743785ef8d38b2de81b6870521f3519dcb63d36cb3
pdf-font-stream PDF embedded font (sfnt) at offset 0x11818 16900 bytes