Malicious PDF — malware analysis report

Static analysis result for SHA-256 e551992ab1378027…

MALICIOUS

PDF

92.0 KB Created: 2021-07-29 21:49:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e5f3b7c581764be24252048811f1d69a SHA-1: 5f790ab4bdad8b78e2cdef2076968702b29fbc5a SHA-256: e551992ab137802737c96286e6858c99f96ffcec28aa655ab99263bc04d47677
156 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to compromised CMS uploads or 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. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://inwebjor.ru/uplcv?utm_term=how+to+write+script+coverage+comments
    • https://bhsbeacon.com/FCKeditor/file/21328863813.pdf
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ada181f8b1---77887493542.pdf
    • https://karapinarinsaat.net/userfiles/upload/file/xudariride.pdf
    • https://stdtekstil.com/upload/ckfinder/files/tafatenu.pdf
    • http://danburyhighclassof1961.com/clients/b/b4/b42d7d7907ff1a67dd6fd366dd3c6775/File/zawujegozimokowazubokebin.pdf
    • https://cihangirhotel.com/upload/ckfinder/files/80156794878.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/b00d521eb5a40f93fe1686644b69b47f/94574080467.pdf
    • http://aaaexpressheating.com/userfiles/file/21243103783.pdf
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/160bee180b4848---bajuxefigotazaseru.pdf
    • https://thesaddlebank.com/wp-content/plugins/super-forms/uploads/php/files/8hunmu6bvnmkpg5jmk0cuvni2b/kejikutapabepuf.pdf
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b9da97bef46---xobivobem.pdf
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072a91c8c498---dafuwugokowix.pdf
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/3efs9651n7a7qd34ccvnh4ve10/tilowudonofilipevi.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c9286889098---68769559181.pdf
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609bab9555909---fitotudowikomom.pdf
    • http://masan315.net/board/imagefile/file/1433232294.pdf
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/nh9e7jiirh5a34ki2qkbq3m846/susev.pdf
    • http://cuacongtrinh.vn/upload/files/79254034943.pdf
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/08b48671dafbf3eeeef54b17100d638b/foxijuno.pdf
    • http://londonjip.com/userData/board/file/87666870561.pdf
    • http://monkey-do.net/userfiles/file/nozixawavopo.pdf
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a02a84545c1---26735103532.pdf
    • 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_off00010336.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10336 16792 bytes
font_01_sfnt_off00011b48.bin
753d5ff1bdcd5a0aeb5c2e15e88fc81ea8b911b3f92121ba3d19420595b60a9b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B48 17640 bytes
font_02_sfnt_off0001497d.bin
ece5eaf0fc8edf9d44add79a58e1dffcb6bd0a862a9bd256e740585c69911b0f
pdf-font-stream PDF embedded font (sfnt) at offset 0x1497D 10812 bytes