Malicious PDF — malware analysis report

Static analysis result for SHA-256 de7a5c5dc2fcecec…

MALICIOUS

PDF

72.1 KB Created: 2021-09-12 18:25:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 45e0b9086f8ba703627565269da27cb2 SHA-1: f8fcd38f74bf31b2dc95d9b982399445981adb0e SHA-256: de7a5c5dc2fcecec9a8a5a8cf1339bf3a3d4c7c356ed71638695b84f0522fde1
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 high likelihood of malicious intent. It functions as a link farm, with several URLs pointing to compromised CMS upload directories, suggesting an attempt to lure users to potentially malicious content or phishing sites. No scripts were extracted, but the structure and URL findings strongly suggest a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://ikra-ekb.ru/files/fckeditor/file/22098565918.pdf
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613270af88017---3700409192.pdf
    • http://personal.sut.ac.th/chantira/port/ckfinder/userfiles/files/90872968050.pdf
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/16138b8842a0cd---94972190085.pdf
    • https://markyatirim.com/resimler/files/mebisetezewopujetuxi.pdf
    • http://rideco.hu/upload/file/33140396345.pdf
    • https://cherrychile.cl/cherry/uploads/contenido/files/2883816547.pdf
    • https://pirkitpadangas.lt/ckfinder/userfiles/files/99681654985.pdf
    • https://idea-web.ro/app/webroot/files/userfiles/files/lavusetifafoperopujuludi.pdf
    • https://ckmusicdesign.nl/userfiles/file/32132365836.pdf
    • https://canoe.ro/Extras/ckfinder/userfiles/files/56169902057.pdf
    • http://ty-universe.com/image/files/20210906_120056.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/1dvi3ms7eujghjn8ffn99esai6/gurawi.pdf
    • http://southerncross-ex.com/images/blog/file/82832014609.pdf
    • http://artediapharma.com/upload/files/giwatoxoruxen.pdf
    • https://bengalroys.com/ckfinder/userfiles/files/88042659539.pdf
    • http://mabifitness.it/userfiles/files/vofinosovatuzadeguxek.pdf
    • http://land89.com/ckupload/files/72542906995.pdf
    • http://frigotechreina.com/userfiles/files/55197650023.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137c3af4a5fa---jozutowamafiwodisemepe.pdf
    • https://www.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/56182209557.pdf
    • http://fourfoods.com/images/files/fijejoj.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=tubemate+app+download+apk
    • 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_off0000b7be.bin
6a67c1d15555be05f086c3cb494fad2d7353479b0c8159a718364bd6f070ad6a
pdf-font-stream PDF embedded font (sfnt) at offset 0xB7BE 10576 bytes
font_01_sfnt_off0000cfae.bin
434d4c1f1601adf3dc9559147e1e0d49b89beceb5f00e541f2ae3a58559e2db3
pdf-font-stream PDF embedded font (sfnt) at offset 0xCFAE 16908 bytes
font_02_sfnt_off0000faab.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFAAB 16792 bytes