Malicious PDF — malware analysis report

Static analysis result for SHA-256 43a7f991b2a3532c…

MALICIOUS

PDF

98.2 KB Created: 2021-07-03 06:29:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d0bc71a27eba1afa74eb0a2f1e9943a9 SHA-1: e45cc7997a6d9096bc0af16d93cef2f5ab276c66 SHA-256: 43a7f991b2a3532cc8ca71f3e26c3f82b7588a9233ede75ff8c2454ffb2a1fcf
96 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to compromised WordPress sites, indicating a distribution mechanism for malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent. No scripts were extracted, and the document body was unreadable, so the primary evidence comes from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9781

Heuristics 5

  • 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://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/8r7vtevu30l0pf3mu3n66bslk4/kubekaremelixi.pdf In PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/160d5fecfa22b0---roduzuko.pdfIn PDF document text
    • http://blackhorsesc.pl/userfiles/file/lepogasupe.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c98f761c1f9---xekowap.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609bcfa7167f3---gefuv.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160adcbc004c2a---88393349874.pdfIn PDF document text
    • http://bigband-ulm.de/userfiles/files/taxavuweditarod.pdfIn PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/8c1bb2534db4d6c0710093257c976867/ralaxanexeto.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081933272783---tesaku.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/3e1qag8mob1nfcr5bh8a3t3h6m/sifomos.pdfIn PDF document text
    • https://thegioidongphuc.net/ckfinder/userfiles/files/kizivuwesazobefa.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dfc2b3e412---70944961366.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba630e19788---gexow.pdfIn PDF document text
    • http://bmcnx.com/userfiles/file/besuzo.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c888726a4f---zunuraxafuzeka.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/e126d9c1532ada1b2fca6c77aa720ed2/kuzidedixavunujikeda.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/ocn79fs7lk8salctjfv4qcc051/mugazu.pdfIn PDF document text
    • https://aprilboya.com/userfiles/file/11808092114.pdfIn PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/f9g1asbv439f39mprn0it0nqle/21639679902.pdfIn PDF document text
    • https://www.carrentchiengmai.com/files/52728484018.pdfIn PDF document text
    • http://turexpert.md/userfiles/images/file/jazejipaza.pdfIn PDF document text
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b75ddb1d5ec---ladapidibinotodusizat.pdfIn PDF document text
    • http://ukrainski-rosyjski.pl/userfiles/file/44672921197.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=cheesy+smile+meaningPDF 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f515.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF515 20888 bytes
SHA-256: eb914af7420f990451bf197b290bbbd0c2509bf22f44948d5332c921c0f98c4a
font_01_sfnt_off00012825.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12825 10380 bytes
SHA-256: 794add8a0941fccedb8fc4558d3a1f97439114a751ca246a0a761c9a3cb8cc44
font_02_sfnt_off00013f64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F64 2336 bytes
SHA-256: d8740fb1fdd9da5007a5f96e73d016a8943ed100214be4167d910547d9a83dc7
font_03_sfnt_off000149b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149B0 17008 bytes
SHA-256: a9c81e950a4e3be70ce753d24331318750e409ca67cdffaed00f268dad5686ba
font_04_sfnt_off000162bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x162BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.