Malicious PDF — malware analysis report

Static analysis result for SHA-256 3efb423a582b2d43…

MALICIOUS

PDF

88.8 KB Created: 2021-06-26 11:52:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 70a15a25774b1c1588c6df4f5c78f83b SHA-1: 77b2e5ef9801cde0c23f68c15d51366d59569582 SHA-256: 3efb423a582b2d43085322d67c26ea9fb181e82c59bb77e021f41dc151a1a2a0
164 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms and appear to be part of a link farm designed to trick users into downloading files. The presence of a 'download button' heuristic further supports the lure. ClamAV detection and ML classification confirm the malicious nature of the document, likely serving as a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ec75d9357---ginijojudufixinozupotaxa.pdf
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093c0329838f---xevezuwiwexo.pdf
    • https://aradmissions.com/ci/userfiles/files/xugifugabigitixisupe.pdf
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/aup2b78er0c01h39fqhbn4m57i/8299356241.pdf
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/947ac471b0862c7f50eb5fdab6a96124/kosorugu.pdf
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16089e8edcea3f---23081258756.pdf
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/slonrj79e31nk1aibes7nfrch3/75605289614.pdf
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16097f74c45f5a---rovonuxitevumovupe.pdf
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/80d052e139c558b48e1d44060d877757/wafugusuja.pdf
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/a024bde2cc9bf7ac5a08679ddd9583d5/wikekofaxubajuxiforoxo.pdf
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/850808f746b58f17395a5a67cd60d2ca/846078087.pdf
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/bd7955c580dade86f3a6af7bb5aab02e/solomisibaran.pdf
    • http://namngonviet.vn/user-/files/3238829341.pdf
    • https://brianhigbielaw.com/UserFiles/file/96650373807.pdf
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/55151674390.pdf
    • http://petukmahaaaraj.com/userfiles/file/taregubakisuwalewo.pdf
    • https://lacecinella.com/writable/public/userfiles/file/dumigorezinatepitofer.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bdb2b1d4bea---xunatenelipefeval.pdf
    • http://www.findvoters.com/userfiles/file/56850005019.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093a721d0ab9---50620563387.pdf
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/vevuranovoj.pdf
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/4acbbd92bf99b97600e392854e7d3126/32474395935.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=i+robot+tamil+dubbed+movie+download
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/1acebfe002be45707565091b28adddc6/39365290473.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_off0000f986.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF986 16792 bytes
font_01_sfnt_off0001119d.bin
606262559742bf81a656398c4907e596b31a0173e672497fc0030697d4ee8490
pdf-font-stream PDF embedded font (sfnt) at offset 0x1119D 10584 bytes
font_02_sfnt_off000129bd.bin
67870c5f86c152146f382ba865906703816c50006209b21754dac678b3b4d68b
pdf-font-stream PDF embedded font (sfnt) at offset 0x129BD 16988 bytes