Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a1f957e1ad02c85…

MALICIOUS

PDF

78.0 KB Created: 2021-07-19 10:12:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 073c25ec809e2313ae78abe70d455f7c SHA-1: 3dc2f835b5ac0169dfcc6a6fff8dcfee850f0b3a SHA-256: 8a1f957e1ad02c8516cc4afcdebab0437f73ab47aa6459462630a46207ac86ff
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to various PDF files hosted on compromised websites and disposable domains, indicative of a phishing or scam campaign. The 'SE_CALLBACK_LURE' heuristic specifically identifies a callback phishing pretext, suggesting the document aims to trick users into calling a fraudulent number. While no scripts were directly extracted, the presence of numerous external links and the ML classifier's high confidence score support the phishing attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 7

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://karimeh.com/public/userfiles/file/palatatafe.pdf
    • https://gretajensen.com/ckfinder/userfiles/files/nebijur.pdf
    • https://gofropack.com/wp-content/plugins/super-forms/uploads/php/files/6a118d43610cd03673d635f0ff12bef9/53491116796.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/nib1qi7frsasapc1np6a04urk4/mikibup.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b2e07c8b6ac---wonevitugi.pdf
    • http://kirakuramenandsushi.com/uploads/files/9351082149.pdf
    • https://karinbentum.nl/uploads/file/wazomonavuviwovagazabitix.pdf
    • https://bodymart.in/ckfinder/userfiles/files/jufejonufopetofidor.pdf
    • https://www.alphaveneers.com/wp-content/plugins/super-forms/uploads/php/files/5c099a8c7ca2c76e7d545e1673ca1bf9/26151460808.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f31cd8b31e8---86110806016.pdf
    • http://thsport.dk/ckfinder/userfiles/files/fititovixagirekixopusivar.pdf
    • http://www.kyousei-fukushi.or.jp/system/ckfinder/userfiles/files/75083788951.pdf
    • http://thetuckerfamilyreunion.com/clients/67950/File/xoledimugakafiwo.pdf
    • https://bosgo.mn/uploads/files/29503983084.pdf
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/88793ac72b78c6f1c89a4d93d61dd7b6/topelujujewidedorobipa.pdf
    • http://ebbers-schilderwerken.nl/uploads/files/31680927425.pdf
    • http://mariopresto.pl/userfiles/file/25874602843.pdf
    • http://maternites-catholiques.org/ressource/site-image/files/tazepuvejaporelexewi.pdf
    • http://e-hematologica.pl/users//file/24934737214.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/16073d0657c44e---61289591759.pdf
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c863f88760a---babodezasorevowidamovaji.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/ig0erkd6fbl2dn4mt064905557/5128625022.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=residential+commercial+and+industrial+electrical+systems+pdf+download
    • 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_off0000c9bf.bin
c1e8b7a62ed3119453e55f78eeeb83d6c4dc8e8e6c2ac593e027a6bc08b60a7f
pdf-font-stream PDF embedded font (sfnt) at offset 0xC9BF 17604 bytes
font_01_sfnt_off0000f7ed.bin
7eef89c286e84fc4455fdc7a6c1a41f3f7dafaafb204ff038f17bd7e8dbc0842
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7ED 11128 bytes
font_02_sfnt_off000111f8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x111F8 16792 bytes