Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3ba0144d23ae877…

MALICIOUS

PDF

88.3 KB Created: 2021-07-18 09:53:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 103b6884da2b02af2c3482599b327ad5 SHA-1: 091cb22cd73f9a1739c6027364d9fadafdb81609 SHA-256: a3ba0144d23ae877e9a924b7c072ccc7b001c4ea450b7aecc686c5378af3d94d
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to obscure the ultimate destination. ClamAV and ML classifiers flagged this PDF as malicious, specifically as a phishing trojan. The presence of multiple compromised upload URLs suggests an attempt to distribute malicious content or redirect users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160cf1867a5b18---59679406013.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/fqervokgbhlfndo1ij9hbu98kp/27971555282.pdf
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/e1c6f20dbb751a3f12cc73976eee1f96/nudawojibedikikipajiz.pdf
    • http://arcomproltd.com/userfiles/file/faruwewumumuxategew.pdf
    • http://poltinik.ru/userfiles/file/20174976816.pdf
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16074aaa1a3a2a---lavojebidusaronut.pdf
    • https://pottoka.info/files/galeria/files/99694580658.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/k8tgohp1oac4udrqvklnk28i57/87191961557.pdf
    • http://euroteam.vn/ckfinder/userfiles//files/woresodulenos.pdf
    • http://ajtoablakcentrum.com/_user/file/fisogagalinexisel.pdf
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/d3bdbc03fd320c7d51b700c9506bcd38/jakotos.pdf
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/16074832b920a7---geleborobexukavaro.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/97b6b0998797b6d3b0cf17965733fef7/momodujakemanelinufujen.pdf
    • https://acornschoolcharleston.org/wp-content/plugins/super-forms/uploads/php/files/a7a5fcbc7d902d42790bf6437aba62cb/93537006096.pdf
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/4cjd011si6anl5psd015vk85o2/70366875287.pdf
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/7183866a77ff3dd5e456eca39ddc11e0/28589364723.pdf
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/8a8d72e72bfe3d06823cb5e70e8d28f1/51062649575.pdf
    • http://myphamlulanjina.com/upload/files/najakega.pdf
    • https://annjulieskarpmo.com/userfiles/file/71139520277.pdf
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/54ugfvuc22j92lqic65263h42k/54828476207.pdf
    • https://local-atlas.ru/userfiles/files/sibumobipoxowe.pdf
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/1bdrds6ccjklj5a2p13v5m8kjq/50168612230.pdf
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609ebf209b11a---48287373674.pdf
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097f74ed0583---govusivumuxawipulokalewar.pdf
    • http://wo-kop.pl/userfiles/file/zogivew.pdf
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/ae8829e5bd2c0a3cc20f0b65c2a69c63/40258130650.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=crossword+puzzle+states+of+matter
    • 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_off0000f5ee.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5EE 16792 bytes
font_01_sfnt_off00010e05.bin
44df53edb8dec3068b1a590ace257e51f7f5334d30814c64461fd017194c539a
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E05 10740 bytes
font_02_sfnt_off000126e3.bin
6477ca94c7f666caa447d6839ee5b5ab14760417f40703deaeee593e6ecba8e4
pdf-font-stream PDF embedded font (sfnt) at offset 0x126E3 17204 bytes