Malicious PDF — malware analysis report

Static analysis result for SHA-256 50cd2c8be79acde6…

MALICIOUS

PDF

84.3 KB Created: 2021-09-07 02:27:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 627a7c1b3eaa8d1558c9ac820d7450c5 SHA-1: ce5206586f79ba83dcb6f8c2c815313c5266cbe3 SHA-256: 50cd2c8be79acde6bbb51c5ed0eed7119f41906e3bae427a02f3749cc28e1ca1
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with attempts to download further payloads or trick users into providing sensitive information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • 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 https://wastran.ru/uplcv?utm_term=derrame+pleural+pdf
    • http://driver-jazda.pl/upload/file/46522626936.pdf
    • http://www.pics4us.de/userfiles/file/fawisu.pdf
    • https://iaetindia.com/ckfinder/userfiles/files/puwagemojuru.pdf
    • https://cplastik.net/data/cms/file/84838374286.pdf
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b077fd87c1e---76431900929.pdf
    • http://airconbank.com/upload/fckeditor/file/86607449396.pdf
    • http://stihoplet.by/upload/editor/files/xitonamegezefu.pdf
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/33p3ts65r46l3i5ol9tf2u980n/41019876823.pdf
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/a6affe1aae0eb8398abaee4296622853/70502686487.pdf
    • http://dh-life.com/ckfinder/userfiles/files/kipawudubejijufe.pdf
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/f8ldlqu2t1vvjgsr2sjug3stbh/latodojevapaga.pdf
    • https://safetyhanoi.com/userfiles/file/fogometenepoladamim.pdf
    • https://asi-filter.pl/files/file/koxigujatufifiluzixunubo.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9a411bd9f---32789301606.pdf
    • http://xn--9n2bn9mz3aba29g44r4o0a.kr/fckeditor/userfiles/image/98307116170.pdf
    • https://o2opr.co/userfiles/files/bizevivonidefanozegomano.pdf
    • http://aven.su/userfiles/file/80451802006.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/dc28l7n90idk2hl67etvmib0ho/jeturisonopevitoru.pdf
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/82841988174.pdf
    • https://denimder.org/resimler/files/tofigi.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/3c532b212e051d6869584737b6658e86/93810941338.pdf
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/72vsdmfvrkn51igl9oh0atrtdj/gitaxaxusazoki.pdf
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/a315e83f48802d5025a393bfbcf570a2/12137015307.pdf
    • https://sharadsangam.org/UserFilesTwo/file/14674655296.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_off0000e30a.bin
416afde5a9bca2824079eebc4bd822823613e2708350a86d7dae3779bdf105ae
pdf-font-stream PDF embedded font (sfnt) at offset 0xE30A 19068 bytes
font_01_sfnt_off000114af.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x114AF 16792 bytes
font_02_sfnt_off00012cc6.bin
970606efa9f7bae5b3bbb6580981d8759e7ec274042443c4bd8d25ef3d395814
pdf-font-stream PDF embedded font (sfnt) at offset 0x12CC6 10180 bytes