Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7ba43fcb262b588…

MALICIOUS

PDF

108.5 KB Created: 2021-08-04 13:04:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 095af3850ceefe661838a4763f29ff6b SHA-1: fa4cd2f42ce20f16a1419a6afbe494aa3235c33e SHA-256: a7ba43fcb262b58888f03e87ad55e93de75cc82780dd3a6548620f4ec8851f9a
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many pointing to compromised CMS upload directories, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple external URIs and link farm characteristics points towards a tactic of directing users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

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://pametnidom.hr/pametne_kuce/userfiles/file/24487221801.pdf In PDF document text
    • http://xn--l3cbpp3gh4a5g5c.com/userfiles/files/15602424414.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/fasrks4cjgnpd31ltobgjut6c5/vofixexalak.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8f7776e541---jobubamame.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/1a1320cfb2a597b80eca19ff03940d44/89323960059.pdfIn PDF document text
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/86200530567.pdfIn PDF document text
    • http://comlark.ru/userfiles/files/tawonematugejizomajebeteb.pdfIn PDF document text
    • http://interwork.sk/userfiles/file/65812326750.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd2e7a5567---nerusirazumufefu.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/g1035mm6iij9bsi71297up3ni7/vozavek.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075d20294776---81424190698.pdfIn PDF document text
    • http://cga82.com/admin/File/linitotiz.pdfIn PDF document text
    • https://austarpharma.com/upload/files/lilelo.pdfIn PDF document text
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/ef2a40f0cb1552e86bca92c72d834fd3/veverirunapufebejowepiga.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ca8cd0c0544---zojenovopej.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160967c94c4b46---gufizutufalemugo.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/e7fe790883e25a7c40bd92a53a74c828/mobifuzuxumiw.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b67ea06a568---78670821909.pdfIn PDF document text
    • https://creteotels.gr/FCKeditor/userimages/file/jodotiwibobewejodin.pdfIn PDF document text
    • https://tradingphrases.com/userfiles/files/99419352753.pdfIn PDF document text
    • http://richmediahouse.com/admin/uploads/file/198513185.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160791e2863754---zajolap.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/kozunejaxibimejefikukaf.pdfIn PDF document text
    • http://turinhotelcompany.com/userfiles/files/77830408144.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/df9f7d2bc7197098577104db3c350794/19958369082.pdfIn PDF document text
    • http://falegnameriacastiglione.it/userfiles/files/ruvug.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=age+of+empires+2+cheatsPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000145b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00015dc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15DC8 17328 bytes
SHA-256: c7e58035fdf45c819a8f800f32f2fc3b4fee24620e22f1ade45cc14b444fc83e
font_02_sfnt_off00018a8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18A8B 10876 bytes
SHA-256: de6404f35286b707bf79d13c441513fda5aac81744ac897883989abf7b588684