Malicious PDF — malware analysis report

Static analysis result for SHA-256 381a4bfae6302e28…

MALICIOUS

PDF

84.1 KB Created: 2021-07-02 03:57:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 37103825b57cb2b22dca7b79eea2d00f SHA-1: ab00eb5bf0be75d0ab8c6d76fc8949e2927f97ee SHA-256: 381a4bfae6302e28357752334c581d7d765f8a8321e2c80f7162932a384a6bdd
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://cam-ceeds.org/ckfinder/userfiles/files/nurifowogufebomomalupawov.pdf
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a0a219f486---lezojazedubetis.pdf
    • http://chia4kids.ru/ckfinder/userfiles/files/botijurifovumujomuzuniv.pdf
    • https://badoza.net/userfiles/file/7616457932.pdf
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16086375e6c477---turewigomawubiwewezaxa.pdf
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aa5669a1b3---30053440178.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16073ffd4a3d6a---12862462910.pdf
    • https://angkaganjil.com/contents//files/91349369478.pdf
    • http://influences-vegetales.eu/assets/Image//files/xusivalupe.pdf
    • https://unserbiokorb.ch/userfiles/file/disijuvunozijemimava.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160871f5423b80---14434447207.pdf
    • https://travelworld.ro/userfiles/file/kefolepuposububusazexo.pdf
    • http://ash-graphy.com/userfiles/file/51791973561.pdf
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/aca612a8f93a0778407b6bf91be1b171/vagajamago.pdf
    • http://artecgroupservices.com/imagenes/file/gonevatagudasumafozobetix.pdf
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/477476f0b66de35c4d7254f1867a6e99/ganorukaxe.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0fd4bd5f7---sigebajapibizezubigo.pdf
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf1564bbb3f---13091230816.pdf
    • http://china-hold.com/UploadFile/file/20210612192402514.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/dac321f90eed0976bbb35073e3b94c55/jarumusamir.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ded4c39a66---voxupatipebipowesoludiz.pdf
    • https://aonetreks.com/uploads/file/3400166537.pdf
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/295a0b6ce7b3ceec1d85a44a99ec06ab/tinodadarurukufadado.pdf
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608668446ddfd---4818407151.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=what+does+a+psychology+degree+entail
    • 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_off0000e695.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE695 16792 bytes
font_01_sfnt_off0000fea7.bin
3ee19e05b5acacf6189e35d52e10d2172915306cf6ded11ac03b7c0b80f91d22
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEA7 16644 bytes
font_02_sfnt_off000129c6.bin
5bbe8c93599f39cbf85c7fb593c8a044237081b6674ef514f83f698d3d15cc80
pdf-font-stream PDF embedded font (sfnt) at offset 0x129C6 10900 bytes